Human Receptor Proteins; Related Reagents and Methods

ABSTRACT

Nucleic acids encoding mammalian Toll-like receptors (TLRs) have been identified in human cells. Recombinantly produced TLRs are used in the preparation of antibodies that are capable of binding to the TLRs. The antibodies are advantageously used in the prevention and treatment of septic shock, inflammatory conditions, and viral infections.

This filing is a continuation-in-part patent application, claimingbenefit of U.S. Utility patent application Ser. No. 09/728,540, filedNov. 28, 2000, which claims benefit of U.S. Provisional PatentApplication U.S. Ser. No. 60/207,558, filed May 25, 2000, which claimspriority to copending U.S. patent application Ser. No. 09/073,363, filedMay 6, 1999, which claims benefit of the following Provisional PatentApplications: U.S. Ser. No. 60/044,293, filed May 7, 1997; U.S. Ser. No.60/072,212, filed Jan. 22, 1998; and U.S. Ser. No. 60/076,947, filedMar. 5, 1998; all of which are incorporated herein by reference.

FIELD OF THE INVENTION

The present invention relates to compositions and methods for affectingmammalian physiology, including morphogenesis or immune system function.In particular, it provides nucleic acids, proteins, and antibodies whichregulate development and/or the immune system. Diagnostic andtherapeutic uses of these materials are also disclosed.

BACKGROUND OF THE INVENTION

Recombinant DNA technology refers generally to techniques of integratinggenetic information from a donor source into vectors for subsequentprocessing, such as through introduction into a host, whereby thetransferred genetic information is copied and/or expressed in the newenvironment. Commonly, the genetic information exists in the form ofcomplementary DNA (cDNA) derived from messenger RNA (mRNA) coding for adesired protein product. The carrier is frequently a plasmid having thecapacity to incorporate cDNA for later replication in a host and, insome cases, actually to control expression of the cDNA and therebydirect synthesis of the encoded product in the host.

For some time, it has been known that the mammalian immune response isbased on a series of complex cellular interactions, called the “immunenetwork”. Recent research has provided new insights into the innerworkings of this network. While it remains clear that much of the immuneresponse does, in fact, revolve around the network-like interactions oflymphocytes, macrophages, granulocytes, and other cells, immunologistsnow generally hold the opinion that soluble proteins, known aslymphokines, cytokines, or monokines, play critical roles in controllingthese cellular interactions. Thus, there is considerable interest in theisolation, characterization, and mechanisms of action of cell modulatoryfactors, an understanding of which will lead to significant advancementsin the diagnosis and therapy of numerous medical abnormalities, e.g.,immune system disorders.

Lymphokines apparently mediate cellular activities in a variety of ways.They have been shown to support the proliferation, growth, and/ordifferentiation of pluripotential hematopoietic stem cells into vastnumbers of progenitors comprising diverse cellular lineages which makeup a complex immune system. Proper and balanced interactions between thecellular components are necessary for a healthy immune response. Thedifferent cellar lineages often respond in a different manner whenlymphokines are administered in conjunction with other agents.

Cell lineages especially important to the immune response include twoclasses of lymphocytes: B-cells, which can produce and secreteimmunoglobulins (proteins with the capability of recognizing and bindingto foreign matter to effect its removal), and T-cells of various subsetsthat secrete lymphokines and induce or suppress the B-cells and variousother cells (including other T-cells) making up the immune network.These lymphocytes interact with many other cell types.

Another important cell lineage is the mast cell (which has not beenpositively identified in all mammalian species), which is agranule-containing connective tissue cell located proximal tocapillaries throughout the body. These cells are found in especiallyhigh concentrations in the lungs, skin, and gastrointestinal andgenitourinary tracts. Mast cells play a central role in allergy-relateddisorders, particularly anaphylaxis as follows: when selected antigenscrosslink one class of immunoglobulins bound to receptors on the mastcell surface, the mast cell degranulates and releases mediators, e.g.,histamine, serotonin, heparin, and prostaglandins, which cause allergicreactions, e.g., anaphylaxis.

Research to better understand and treat various immune disorders hasbeen hampered by the general inability to maintain cells of the immunesystem in vitro. Immunologists have discovered that culturing many ofthese cells can be accomplished through the use of T-cell and other cellsupernatants, which contain various growth factors, including many ofthe lymphokines.

The interleukin-1 family of proteins includes the IL-1α, the IL-1β, theIL-1RA, and recently the IL-1γ (also designated Interferon-GammaInducing Factor, IGIF). This related family of genes have beenimplicated in a broad range of biological functions. See Dinarello,FASEB J. 8, 1314 (1994); Dinarello, Blood 77, 1627 (1991); and Okamura,et al., Nature 378, 88 (1995).

In addition, various growth and regulatory factors exist which modulatemorphogenetic development. This includes, e.g., the Toll ligands, whichsignal through binding to receptors which share structural, andmechanistic, features characteristic of the IL-1 receptors. See, e.g.,Lemaitre, et al., Cell 86, 973 (1996); and Belvin and Anderson, Ann.Rev. Cell & Devel. Biol. 12, 393 (1996).

From the foregoing, it is evident that the discovery and development ofnew soluble proteins and their receptors, including ones similar tolymphokines, should contribute to new therapies for a wide range ofdegenerative or abnormal conditions which directly or indirectly involvedevelopment, differentiation, or function, e.g., of the immune systemand/or hematopoietic cells. In particular, the discovery andunderstanding of novel receptors for lymphokine-like molecules whichenhance or potentiate the beneficial activities of other lymphokineswould be highly advantageous. The present invention provides newreceptors for ligands exhibiting similarity to interleukin-1 likecompositions and related compounds, and methods for their use.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a schematic comparison of the protein architectures ofDrosophila, Caenorabditis, and human TLRs, and their relationship tovertebrate IL-1 receptors and plant disease resistance proteins. ThreeDrosophila (Dm) TLRs (Toll, 18w, and the Mst ORF fragment) (Morisato andAnderson, Ann. Rev. Genet. 29, 371 (1995); Chiang and Beachy, Mech.Develop. 47, 225 (1994); Mitcham, et al., J. Biol. Chem. 271, 5777(1996); and Eldon, et al., Develop. 120, 885 (1994)) are arrayed besidefour complete (TLRs 1-4) and one partial (TLR5) human (Hu) receptors.Individual LRRs in the receptor ectodomains that are flagged by PRINTS(Attwood, et al., Nucleic Acids Res. 25, 212 (1997)) are explicitlynoted by boxes; ‘top’ and ‘bottom’ Cys-rich clusters that flank the C—or N-terminal ends of LRR arrays are respectively drawn by opposedhalf-circles. The loss of the internal Cys-rich region in TLRs 1-5largely accounts for their smaller ectodomains (558, 570, 690, and 652aa, respectively) when compared to the 784 and 977 aa extensions of Tolland 18w. The incomplete chains of DmMst and HuTLR5 (about 519 and 153 aaectodomains, respectively) are represented by dashed lines. Theintracellular signaling module common to TLRs, IL-1-type receptors(IL-1Rs), the intracellular protein Myd88, and the tobacco diseaseresistance gene N product (DRgN) is indicated below the membrane. See,e.g., Hardiman, et al., Oncogene 13, 2467(1996); and Rock, et al., Proc.Nat'l Acad. Sci. USA 95, 588 (1998). Additional domains include the trioof Ig-like modules in IL-1Rs (disulfide-linked loops); the DRgN proteinfeatures an NTPase domain (box) and Myd88 has a death domain (blackoval).

FIGS. 2A-2C show conserved structural patterns in the signaling domainsof Toll- and IL-1-like cytokine receptors, and two divergent modularproteins. FIGS. 2A-2B show a sequence alignment of the common TH domain.TLRs are labeled as in FIG. 1; the human (Hu) or mouse (Mo) IL-1 familyreceptors (IL-1R1-6) are sequentially numbered as earlier proposed(Hardiman, et al., Oncogene 13, 2467 (1996)); Myd88 and the sequencesfrom tobacco (To) and flax, L. usitatissimum (Lu), represent C— andN-terminal domains, respectively, of larger, multidomain molecules.Ungapped blocks of sequence (numbered 1-10) are boxed. Trianglesindicate deleterious mutations, while truncations N-terminal of thearrow eliminate bioactivity in human IL-1R1 (Heguy, et al., J. Biol.Chem. 267, 2605(1992)). PHD (Rost and Sander, Proteins 19, 55 (1994))and DSC (King and Sternberg, Protein Sci. 5, 2298 (1996)) secondarystructure predictions of α-helix (H), β-strand (E), or coil (L) aremarked. The amino acid shading scheme depicts chemically similarresidues: hydrophobic, acidic, basic, Cys, aromatic, structure-breaking,and tiny. Diagnostic sequence patterns for IL-1Rs, TLRs, and fullalignment (ALL) were derived by Consensus at a stringency of 75%.Symbols for amino acid subsets are (see internet site for detail): o,alcohol; l, aliphatic; •, any amino acid; a, aromatic; c, charged; h,hydrophobic; −, negative, p, polar; +, positive; s, small; u, tiny; t,turnlike. FIG. 2C shows a topology diagram of the proposed TH β/α domainfold. The parallel β-sheet (with β-strands A-E as yellow triangles) isseen at its C-terminal end; α-helices (circles labeled 1-5) link theβ-strands; chain connections are to the front (visible) or back(hidden). Conserved, charged residues at the C-end of the β-sheet arenoted in gray (Asp) or as a lone black (Arg) residue (see text).

FIG. 3 shows evolution of a signaling domain superfamily. The multipleTH module alignment of FIGS. 2A-2B was used to derive a phylogenetictree by the Neighbor-Joining method (Thompson, et al., Nucleic AcidsRes. 22,4673 (1994)). Proteins labeled as in the alignment; the tree wasrendered with TreeView.

FIGS. 4A-4D depict FISH chromosomal mapping of human TLR genes.Denatured chromosomes from synchronous cultures of human lymphocyteswere hybridized to biotinylated TLR cDNA probes for localization. Theassignment of the FISH mapping data (left, FIGS. 4A, TLR2; 4B, TLR3; 4C,TLR4; 40, TLR5) with chromosomal bands was achieved by superimposingFISH signals with DAPI banded chromosomes (center panels) (Heng andTsui, Meth. Molec. Biol. 33, 109 (1994)). Analyses are summarized in theform of human chromosome ideograms (right panels).

FIGS. 5A-5F depict mRNA blot analyses of Human TLRs. Human multipletissue blots (He, heart; Br, brain; Pl, placenta; Lu, lung; Li, liver;Mu, muscle; Ki, kidney; Pn, Pancreas; Sp, spleen; Th, thymus; Pr,prostate; Te, testis; Ov, ovary, SI, small intestine; Co, colon; PBL,peripheral blood lymphocytes) and cancer cell line (promyelocyticleukemia, HL60; cervical cancer, HELAS3; chronic myelogenous leukemia,K562; lymphoblastic leukemia, Molt4; colorectal adenocarcinoma, SW480;melanoma, G361; Burkitt's Lymphoma Raji, Burkitt's; colorectaladenocarcinoma, SW480; lung carcinoma, A549) containing approximately 2μg of poly(A)⁺ RNA per lane were probed with radiolabeled cDNAs encodingTLR1 (FIGS. 5A-5C), TLR2 (FIG. 5D), TLR3 (FIG. 5E), and TLR4 (FIG. 5F)as described. Blots were exposed to X-ray film for 2 days (FIGS. 5A-5C)or one week (FIG. 5D-5F) at −70° C. with intensifying screens. Ananomalous 0.3 kB species appears in some lanes; hybridizationexperiments exclude a message encoding a TLR cytoplasmic fragment.

SUMMARY OF THE INVENTION

The present invention is directed to nine novel related mammalianreceptors, e.g., primate, human, Toll receptor like molecularstructures, designated TLR2, TLR3, TLR4, TLR5, TLR7, TLR8, TLR9, andTLR10, and their biological activities. It includes nucleic acids codingfor the polypeptides themselves and methods for their production anduse. The nucleic acids of the invention are characterized, in part, bytheir homology to cloned complementary DNA (cDNA) sequences enclosedherein.

In certain embodiments, the invention provides a composition of matterselected from the group of: a substantially pure or recombinant TLR2protein or peptide exhibiting identity over a length of at least about12 amino acids to SEQ ID NO: 4; a natural sequence TLR2 of SEQ ID NO: 4;a fusion protein comprising TLR2 sequence; a substantially pure orrecombinant TLR3 protein or peptide exhibiting identity over a length ofat least about 12 amino acids to SEQ ID NO: 6; a natural sequence TLR3of SEQ ID NO: 6; a fusion protein comprising TLR3 sequence; asubstantially pure or recombinant TLR4 protein or peptide exhibitingidentity over a length of at least about 12 amino acids to SEQ ID NO:26; a natural sequence TLR4 of SEQ ID NO: 26; a fusion proteincomprising TLR4 sequence; a substantially pure or recombinant TLR5protein or peptide exhibiting identity over a length of at least about12 amino acids to SEQ ID NO: 10; a natural sequence TLR5 of SEQ ID NO:10; a fusion protein comprising TLR5 sequence; a substantially pure orrecombinant TLR6 protein or peptide exhibiting identity over a length ofat least about 12 amino acids to SEQ ID NO: 12, 28, or 30; a naturalsequence TLR6 of SEQ ID NO: 12, 28, or 30; a fusion protein comprisingTLR6 sequence; a substantially pure or recombinant TLR7 protein orpeptide exhibiting identity over a length of at least about 12 aminoacids to SEQ ID NO: 16, 18, or 37; a natural sequence TLR7 of SEQ ID NO:16, 18, or 37; a fusion protein comprising TLR7 sequence; asubstantially pure or recombinant TLR8 protein or peptide exhibitingidentity over a length of at least about 12 amino acids to SEQ ID NO: 32or 39; a natural sequence TLR8 of SEQ ID NO: 32 or 39; a fusion proteincomprising TLR8 sequence; a substantially pure or recombinant TLR9protein or peptide exhibiting identity over a length of at least about12 amino acids to SEQ ID NO: 22 or 41; a natural sequence TLR9 of SEQ IDNO: 22 or 41; a fusion protein comprising TLR9 sequence; a substantiallypure or recombinant TLR10 protein or peptide exhibiting identity over alength of at least about 12 amino acids to SEQ ID NO: 34, 43, or 45; anatural sequence TLR10 of SEQ ID NO: 34, 43, or 45; and a fusion proteincomprising TLR10 sequence. Preferably, the substantially pure orisolated protein comprises a segment exhibiting sequence identity to acorresponding portion of a TLR2, TLR3, TLR4, TLR5, TLR6, TLR7, TLR8,TLR9, or TLR10, wherein said identity is over at least about 15 aminoacids; preferably about 19 amino acids; or more preferably about 25amino acids. In specific embodiments, the composition of matter; isTLR2, which comprises a mature sequence of SEQ ID NO:4; or lacks apost-translational modification; is TLR3, which comprises a maturesequence of SEQ ID NO:6; or lacks a post-translational modification; isTLR4, which: comprises a mature sequence of SEQ ID NO:8 or SEQ ID NO:26;or lacks a post-translational modification; is TLR9, which: comprisesthe complete sequence of SEQ ID NO:10; or lacks a post-translational; isTLR6, which comprises a mature sequence of SEQ ID NO: 12, 14, 28, or 30;or lacks a post-translational modification; is TLR7, which comprises amature sequence of SEQ ID NO:16, 18, or 37; or lacks apost-translational modification; is TLR8, which: comprises a maturesequence of SEQ ID NO:20, 32, or 39; or lacks a post-translationalmodification; is TLR9, which: comprises the complete sequence of SEQ IDNO:22 or SEQ ID NO:41; or lacks a post-translational; is TLR10, whichcomprises a mature sequence of SEQ ID NO:24, 34, 43, or 45; or lacks apost-translational modification; or the composition of matter may be aprotein or peptide which: is from a warm blooded animal selected from amammal, including a primate, such as a human; comprises at least onepolypeptide segment of SEQ ID NO: 4, 6, 26, 10, 12, 28, 30, 16, 18, 32,22, or 34; exhibits a plurality of portions exhibiting said identity; isa natural allelic variant of TLR2, TLR3, TLR4, TLR5, TLR6, TLR7, TLR8,TLR9, or TLR10; has a length at least about 30 amino acids; exhibits atleast two non-overlapping epitopes which are specific for a primateTLR2, TLR3, TLR4, TLR5, TLR6, TLR7, TLR8, TLR9, or TLR10; exhibitssequence identity over a length of at least about 35 amino acids to aprimate TLR2, TLR3, TLR4, TLR5, TLR6, TLR7, TLR8, TLR9, or TLR10;further exhibits at least two non-overlapping epitopes which arespecific for a primate TLR2, TLR3, TLR4, TLR5, TLR6, TLR7, TLR8, TLR9,or TLR10; exhibits identity over a length of at least about 20 aminoacids to a rodent TLR6; is glycosylated; has a molecular weight of atleast 100 kD with natural glycosylation; is a synthetic polypeptide; isconjugated to another chemical moiety; is a 5-fold or less substitutionfrom natural sequence; or is a deletion or insertion variant from anatural sequence. In specific embodiments, the TLR, antigenic fragmentof TLR, antibody to TLR, antibody fragment to TLR, antibody to a TLRligand also includes an immobilized form. Immobilization may be byconjugation or attachment to a bead, to a magnetic bead, to a slide, orto a container. Immobilization may be to cyanogen bromide-activatedSEPHAROSE by methods well known in the art, or adsorbed to polyolefinsurfaces, with or without glutaraldehyde cross-linking.

Other embodiments include a composition comprising: a sterile TLR2protein or peptide; or the TLR2 protein or peptide and a carrier,wherein the carrier is: an aqueous compound, including water, saline,and/or buffer; and/or formulated for oral, rectal, nasal, topical, orparenteral administration; a sterile TLR3 protein or peptide; or theTLR3 protein or peptide and a carrier, wherein the carrier is: anaqueous compound, including water, saline, and/or buffer; and/orformulated for oral, rectal, nasal, topical, or parenteraladministration; a sterile TLR4 protein or peptide; or the TLR4 proteinor peptide and a carrier, wherein the carrier is: an aqueous compound,including water, saline, and/or buffer; and/or formulated for oral,rectal, nasal, topical, or parenteral administration; a sterile TLR5protein or peptide; or the TLR5 protein or peptide and a carrier,wherein the carrier is: an aqueous compound, including water, saline,and/or buffer; and/or formulated for oral, rectal, nasal, topical, orparenteral administration; a sterile TLR6 protein or peptide; or theTLR6 protein or peptide and a carrier, wherein the carrier is: anaqueous compound, including water, saline, and/or buffer; and/orformulated for oral, rectal, nasal, topical, or parenteraladministration; a sterile TLR7 protein or peptide; or the TLR7 proteinor peptide and a carrier, wherein the carrier is: an aqueous compound,including water, saline, and/or buffer; and/or formulated for oral,rectal, nasal, topical, or parenteral administration; a sterile TLR8protein or peptide; or the TLR8 protein or peptide and a carrier,wherein the carrier is: an aqueous compound, including water, saline,and/or buffer; and/or formulated for oral, rectal, nasal, topical, orparenteral administration; a sterile TLR9 protein or peptide, or theTLR9 protein or peptide and a carrier, wherein the carrier is: anaqueous compound, including water, saline, and/or buffer; and/orformulated for oral, rectal, nasal, topical, or parenteraladministration; a sterile TLR10 protein or peptide; or the TLR10 proteinor peptide and a carrier, wherein the carrier is: an aqueous compound,including water, saline, and/or buffer; and/or formulated for oral,rectal, nasal, topical, or parenteral administration.

In certain fusion protein embodiments, the invention provides a fusionprotein comprising: mature protein sequence of SEQ ID NO: 4, 6, 8, 10,12, 14, 16, 18, 20, 22, 24, 26, 28, 30, 32, 34, 37, 39, 41, 43, or 45; adetection or purification tag, including a FLAG, His6, or Ig sequence;or sequence of another receptor protein.

Various kit embodiments include a kit comprising a TLR protein orpolypeptide, and: a compartment comprising the protein or polypeptide;and/or instructions for use or disposal of reagents in the kit.

Binding compound embodiments include those comprising an antigen bindingsite from an antibody, which specifically binds to a natural TLR2, TLR3,TLR4, TLR5, TLR6, TLR7, TLR8, TLR9, or TLR10 protein, wherein: theprotein is a primate protein; the binding compound is an Fv, Fab, orFab2 fragment; the binding compound is conjugated to another chemicalmoiety; or the antibody: is raised against a peptide sequence of amature polypeptide of SEQ ID NO: 4, 6, 8, 10, 12, 14, 16, 18, 20, 22,24, 26, 28, 30, 32, 34, 37, 39, 41, 43, or 45; is raised against amature TLR2, TLR3, TLR4, TLR5, TLR6, TLR7, TLR8, TLR9, or TLR10; israised to a purified human TLR2, TLR3, TLR4, TLR5, TLR6, TLR7, TLR8,TLR9, or TLR10; is immunoselected; is a polyclonal antibody; binds to adenatured TLR2, TLR3, TLR4, TLR5, TLR6, TLR7, TLR8, TLR9, or TLR10;exhibits a Kd to antigen of at least 30 μM; is attached to a solidsubstrate, including a bead or plastic membrane; is in a sterilecomposition; or is detectably labeled, including a radioactive orfluorescent label. A binding composition kit often comprises the bindingcompound, and: a compartment comprising said binding compound; and/orinstructions for use or disposal of reagents in the kit. Often the kitis capable of making a qualitative or quantitative analysis.

Methods are provided, e.g., of making an antibody, comprising immunizingan immune system with an immunogenic amount of a primate TLR2, TLR3,TLR4, TLR5, TLR6, TLR7, TLR8, TLR9, or TLR10, thereby causing saidantibody to be produced; or producing an antigen:antibody complex,comprising contacting such an antibody with a mammalian TLR2, TLR3,TLR4, TLR5, TLR6, TLR7, TLR8, TLR9, or TLR10 protein or peptide, therebyallowing said complex to form.

Other compositions include a composition comprising: a sterile bindingcompound, or the binding compound and a carrier, wherein the carrier is:an aqueous compound, including water, saline, and/or buffer; and/orformulated for oral, rectal, nasal, topical, or parenteraladministration.

Nucleic acid embodiments include an isolated or recombinant nucleic acidencoding a TLR2-10 protein or peptide or fusion protein, wherein: theTLR is from a mammal; or the nucleic acid: encodes an antigenic peptidesequence of SEQ ID NO: 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28,30, 32, 34, 37, 39, 41, 43, or 45; encodes a plurality of antigenicpeptide sequences of SEQ ID NO: 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24,26, 28, 30, 32, 34, 37, 39, 41, 43, or 45; comprises at least 17contiguous nucleotides from SEQ ID NO: 3, 5, 7, 9, 11, 13, 15, 17, 19,21, 23, 25, 27, 29, 31, 33, 35, 36, 38, 40, 42, or 44; exhibits at leastabout 80% identity to a natural cDNA encoding said segment; is anexpression vector; further comprises an origin of replication; is from anatural source; comprises a detectable label such as a radioactivelabel, a fluorescent label, or an immunogenic label; comprises syntheticnucleotide sequence; is less than 6 kb, preferably less than 3 kb; isfrom a mammal, including a primate; comprises a natural full lengthcoding sequence; is a hybridization probe for a gene encoding said TLR;or is a PCR primer, PCR product, or mutagenesis primer. A cell, tissue,or organ comprising such a recombinant nucleic acid is also provided.Preferably, the cell is: a prokaryotic cell; a eukaryotic cell; abacterial cell; a yeast cell; an insect cell; a mammalian cell; a mousecell; a primate cell; or a human cell. Kits are provided comprising suchnucleic acids, and: a compartment comprising said nucleic acid; acompartment further comprising a primate TLR2, TLR3, TLR4, or TLR5protein or polypeptide; and/or instructions for use or disposal ofreagents in the kit. Often, the kit is capable of making a qualitativeor quantitative analysis.

Other embodiments include a nucleic acid which: hybridizes under washconditions of 30° C. and less than 2M salt to SEQ ID NO: 3; hybridizesunder wash conditions of 30° C. and less than 2 M salt to SEQ ID NO: 5;hybridizes under wash conditions of 30° C. and less than 2M salt to SEQID NO: 7; hybridizes under wash conditions of 30° C. and less than 2 Msalt to SEQ ID NO: 9; hybridizes under wash conditions of 30° C. andless than 2 M salt to SEQ ID NO: 11, 13, 27, or 29; hybridizes underwash conditions of 30° C. and less than 2 M salt to SEQ ID NO: 15, 17,or 36; hybridizes under wash conditions of 30° C. and less than 2 M saltto SEQ ID NO: 19, 31, or 38; hybridizes under wash conditions of 30° C.and less than 2 M salt to SEQ ID NO: 21 or 40; hybridizes under washconditions of 30° C. and less than 2 M salt to SEQ ID NO: 23, 33, 42, or44; exhibits at least about 85% identity over a stretch of at leastabout 30 nucleotides to a primate TLR2; exhibits at least about 85%identity over a stretch of at least about 30 nucleotides to a primateTLR3; exhibits at least about 85% identity over a stretch of at leastabout 30 nucleotides to a primate TLR4; or exhibits at least about 85%identity over a stretch of at least about 30 nucleotides to a primateTLR5. Preferably, such nucleic acid will have such properties, wherein:wash conditions are at 45° C. and/or 500 mM salt; or the identity is atleast 90% and/or the stretch is at least 55 nucleotides.

More preferably, the wash conditions are at 55° C. and/or 150 mM salt;or the identity is at least 95% and/or the stretch is at least 75nucleotides.

Also provided are methods of producing a ligand:receptor complex,comprising contacting a substantially pure primate TLR2, TLR3, TLR4,TLR5, TLR6, TLR7, TLR8, TLR9, or TLR10, including a recombinant orsynthetically produced protein, with candidate Toll ligand; therebyallowing said complex to form.

The invention also provides a method of modulating physiology ordevelopment of a cell or tissue culture cells comprising contacting thecell with an agonist or antagonist of a mammalian TLR2, TLR3, TLR4,TLR5, TLR6, TLR7, TLR8, TLR9, or TLR10. Preferably, the cell is a pDC2cell with the agonist or antagonist of TLR10.

Abbreviations: TLR, Toll-like receptor; DTLR, DNAX Toll-like receptor;IL-1R, interleukin-1 receptor; TH, Toll homology, LRR, leucine-richrepeat; EST, expressed sequence tag; STS, sequence tagged site; FISH,fluorescence in situ hybridization; GMCSF, granulocyte-macrophagecolony-stimulating factor; NIPC or IPC, natural interferon producingcells.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Outline

-   I. General-   II. Activities-   III. Nucleic acids

A. encoding fragments, sequence, probes

B. mutations, chimeras, fusions

C. making nucleic acids

D. vectors, cells comprising

-   IV. Proteins, Peptides

A. fragments, sequence, immunogens, antigens

B. muteins

C. agonist/antagonists, functional equivalents

D. making proteins

E. soluble receptors

-   V. Making nucleic acids, proteins

A. synthetic

B. recombinant

C. natural sources

-   VI. Antibodies

A. polyclonals

B. monoclonal

C. fragments; Kd

D. anti-idiotypic antibodies

E. hybridoma cell lines

-   VII. Kits and Methods to quantify TLRs 2-10

A. ELISA

B. assay mRNA encoding

C. qualitative/quantitative

D. kits

-   VIII. Therapeutic compositions, methods

A. combination compositions

B. unit dose

C. administration

-   IX. Ligands

I. General

The present invention provides the amino acid sequence and DNA sequenceof mammalian, herein primate Toll like receptor molecules (TLR) havingparticular defined properties, both structural and biological. Thesehave been designated herein as TLR2, TLR3, TLR4, TLR5, TLR6, TLR7, TLR8,TLR9, and TLR10, respectively, and increase the number of members of thehuman Toll like receptor family from 1 to 10. Various cDNAs encodingthese molecules were obtained from primate, e.g., human, cDNA sequencelibraries. Other primate or other mammalian counterparts would also bedesired.

Some of the standard methods applicable are described or referenced,e.g., in Maniatis, et al., Molecular Cloning, A Laboratory Manual, ColdSpring Harbor Laboratory, Cold Spring Harbor Press (1982); Sambrook, etal., Molecular Cloning: A Laboratory Manual, (2d ed.), vols. 1-3, CSHPress, NY (1989); and Ausubel, et al., Current Protocols in MolecularBiology, Greene/Wiley, New York (1987); each of which is incorporatedherein by reference.

A complete nucleotide (SEQ ID NO: 1) and corresponding amino acidsequence (SEQ. ID NO: 2) of a human TLR1 coding segment is shown in theindicated sequence listings. See also Nomura, et al., DNA Res. 1,27(1994). A complete nucleotide (SEQ ID NO: 3) and corresponding aminoacid sequence (SEQ ID NO: 4) of a human TLR2 coding segment is alsoshown, as indicated. A complete nucleotide (SEQ ID NO: 5) andcorresponding amino acid sequence (SEQ ID NO: 6) of a human TLR3 codingsegment are shown, as indicated. A complete nucleotide (SEQ ID NO: 7)and corresponding amino acid sequence (SEQ ID NO: 8) of a human TLR4coding segment are also shown, in the indicated sequence listings. Seealso SEQ ID NO: 25 and 26. A partial nucleotide (SEQ ID NO: 9) andcorresponding amino acid sequence (SEQ ID NO: 10) of a human TLR5 codingsegment are shown in the indicated sequence listings. A completenucleotide (SEQ ID NO: 11) and corresponding amino acid sequence (SEQ IDNO: 12) of a human TLR6 coding segment are shown, along with partialsequence of a mouse TLR6 (SEQ ID NO: 13, 14, 27, 28, 29, and 30), asindicated. Partial nucleotide (SEQ ID NO: 15 and 17) and correspondingamino acid sequence (SEQ ID NO: 16 and 18) of a human TLR7 codingsegment are shown in the indicated sequence listings, while full lengthsequences are provided in SEQ ID NO: 36 and 37. Partial nucleotide (SEQID NO: 19) and corresponding amino acid sequence (SEQ ID NO: 20) of ahuman TLR8 coding segment is shown, with supplementary sequence (SEQ IDNO: 31, 32, 38, and 39). Partial nucleotide (SEQ ID NO: 21) andcorresponding amino acid sequence (SEQ ID NO: 22) of a human TLR9 codingsegment is shown in the indicated sequence listings. See also SEQ ID NO:40 and 41. Partial nucleotide (SEQ ID NO: 23) and corresponding aminoacid sequence (SEQ ID NO: 24) of a human TLR10 coding segment is shownas indicated, along with supplementary sequences (SEQ ID NO: 33, 34, 42,and 43) and rodent, e.g., mouse, sequence (SEQ ID NO: 35, 44, and 45).

Transmembrane segments correspond approximately to 802-818 (791-823) ofprimate TLR7 SEQ ID NO: 37; 559-575 (550-586) of TLR8 SEQ ID NO: 39;553-569 (549-582) of TLR9 SEQ ID NO: 41; 796-810 (790-814) of TLR10 SEQID NO: 43; and 481-497 (475-503) of TLR10 SEQ ID NO: 45.

As used herein, the term Toll like receptor 2 (TLR2) shall be used todescribe a protein comprising a protein or peptide segment having orsharing the amino acid sequence shown in SEQ ID NO: 4, or a substantialfragment thereof. Similarly, with a TLR3 and SEQ ID NO: 6; TLR4 and SEQID NO: 8; TLR5 and SEQ ID NO: 9; TLR6 and SEQ ID NO: 12; TLR7 and SEQ IDNO: 37; TLR8 and SEQ ID NO: 20; TLR9 and SEQ ID NO: 22; and TLR10 andSEQ ID NO: 24. Rodent, e.g., mouse, TLR11 sequence is provided, e.g., inEST AA739083; TLR13 in ESTAI019567; TLR14 in ESTs AI390330 and AA244663.

The invention also includes a protein variations of the respective TLRallele whose sequence is provided, e.g., a mutein agonist or antagonist.Typically, such agonists or antagonists will exhibit less than about 10%sequence differences, and thus will often have between 1- and 11-foldsubstitutions, e.g., 2-, 3-, 5-, 7-fold, and others. It also encompassesallelic and other variants, e.g., natural polymorphic, of the proteindescribed. Typically, it will bind to its corresponding biologicalreceptor with high affinity, e.g., at least about 100 nM, usually betterthan about 30 nM, preferably better than about 10 nM, and morepreferably at better than about 3 nM. The term shall also be used hereinto refer to related naturally occurring forms, e.g., alleles,polymorphic variants, and metabolic variants of the mammalian protein.

This invention also encompasses proteins or peptides having substantialamino acid sequence identity with the amino acid sequence in Table 2. Itwill include sequence variants with relatively few substitutions, e.g.,preferably less than about 3-5. Similar features apply to the other TLRsequences provided in Tables 3, 4, 5, 6, 7, 8, 9, or 10.

A substantial polypeptide “fragment”, or “segment”, is a stretch ofamino acid residues of at least about 8 amino acids, generally at least10 amino acids, more generally at least 12 amino acids, often at least14 amino acids, more often at least 16 amino acids, typically at least18 amino acids, more typically at least 20 amino acids, usually at least22 amino acids, more usually at least 24 amino acids, preferably atleast 26 amino acids, more preferably at least 28 amino acids, and, inparticularly preferred embodiments, at least about 30 or more aminoacids. Sequences of segments of different proteins can be compared toone another over appropriate length stretches.

Amino acid sequence homology, or sequence identity, is determined byoptimizing residue matches, if necessary, by introducing gaps asrequired. See, e.g., Needleham, et al., J. Mol. Biol. 48,443 (1970);Sankoff, et al., Chapter One in Time Warps, String Edits, andMacromolecules: The Theory and Practice of Sequence Comparison,Addison-Wesley, Reading, Mass. (1983); and software packages fromIntelliGenetics, Mountain View, Calif.; GCG WISCONSIN PACKAGE (Accelrys,Inc., San Diego, Calif.); and the NCBI (NIH); each of which isincorporated herein by reference. This changes when consideringconservative substitutions as matches. Conservative substitutionstypically include substitutions within the following groups: glycine,alanine; valine, isoleucine, leucine; aspartic acid, glutamic acid;asparagine, glutamine; serine, threonine; lysine, arginine; andphenylalanine, tyrosine. Homologous amino acid sequences are intended toinclude natural allelic and interspecies variations in the cytokinesequence. Typical homologous proteins or peptides will have from 50-100%homology (if gaps can be introduced), to 60-100% homology (ifconservative substitutions are included) with an amino acid sequencesegment of SEQ ID NO. 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28,30, 32, 34, 37, 39, 41, 43, or 45. Homology measures will be at leastabout 70%, generally at least 76%, more generally at least 81%, often atleast 85%, more often at least 88%, typically at least 90%, moretypically at least 92%, usually at least 94%, more usually at least 95%,preferably at least 96%, and more preferably at least 97%, and inparticularly preferred embodiments, at least 98% or more. The degree ofhomology will vary with the length of the compared segments. Homologousproteins or peptides, such as the allelic variants, will share mostbiological activities with the embodiments described in SEQ ID NO. 4, 6,8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30, 32, 34, 37, 39, 41, 43,or 45. Particularly interesting regions of comparison, at the amino acidor nucleotide levels, correspond to those within each of the blocks1-10, or intrablock regions, corresponding to those indicated in FIGS.2A-2B.

As used herein, the term “biological activity” is used to describe,without limitation, effects on inflammatory responses, innate immunity,and/or morphogenic development by respective ligands. For example, thesereceptors should, like IL-1 receptors, mediate phosphatase orphosphorylase activities, which activities are easily measured bystandard procedures. See, e.g., Hardie, et al., The Protein KinaseFactBook vols. I and II, Academic Press, San Diego, Calif. (1995);Hanks, et al., Meth. Enzymol. 200, 38(1991); Hunter, et al., Cell 70,375 (1992); Lewin, Cell 61, 743 (1990); Pines, et al., Cold SpringHarbor Symp. Quant. Biol. 56, 449 (1991); and Parker, et al., Nature363, 736 (1993). The receptors exhibit biological activities much likeregulatable enzymes, regulated by ligand binding. However, the enzymeturnover number is more close to an enzyme than a receptor complex.Moreover, the numbers of occupied receptors necessary to induce suchenzymatic activity is less than most receptor systems, and may numbercloser to dozens per cell, in contrast to most receptors which willtrigger at numbers in the thousands per cell. The receptors, or portionsthereof, may be useful as phosphate labeling enzymes to label general orspecific substrates.

The terms ligand, agonist, antagonist, and analog of, e.g., a TLR,include molecules that modulate the characteristic cellular responses toToll ligand like proteins, as well as molecules possessing the morestandard structural binding competition features of ligand-receptorinteractions, e.g., where the receptor is a natural receptor or anantibody. The cellular responses likely are mediated through binding ofvarious Toll ligands to cellular receptors related to, but possiblydistinct from, the type I or type II IL-1 receptors. See, e.g., Belvinand Anderson, Ann. Rev. Cell Dev. Biol. 12, 393 (1996); Morisato andAnderson, Ann. Rev. Genetics 29, 371 (1995) and HuItmark, Nature 367,116 (1994).

Also, a ligand is a molecule which serves either as a natural ligand towhich said receptor, or an analog thereof, binds, or a molecule which isa functional analog of the natural ligand. The functional analog may bea ligand with structural modifications, or may be a wholly unrelatedmolecule which has a molecular shape which interacts with theappropriate ligand binding determinants. The ligands may serve asagonists or antagonists, see, e.g., Goodman, et al., Goodman & Gilman's:The Pharmacologic Bases of Therapeutics, Pergamon Press, New York(1990).

Rational drug design may also be based upon structural studies of themolecular shapes of a receptor or antibody and other effectors orligands. Effectors may be other proteins which mediate other functionsin response to ligand binding, or other proteins which normally interactwith the receptor. One means for determining which sites interact withspecific other proteins is a physical structure determination, e.g.,x-ray crystallography or 2 dimensional NMR techniques. These willprovide guidance as to which amino acid residues form molecular contactregions. For a detailed description of protein structural determination,see, e.g., Blundell and Johnson, Protein Crystallography, AcademicPress, New York (1976), which is hereby incorporated herein byreference.

II. Activities

The Toll like receptor proteins will have a number of differentbiological activities, e.g., in phosphate metabolism, being added to orremoved from specific substrates, typically proteins. Such willgenerally result in modulation of an inflammatory function, other innateimmunity response, or a morphological effect. The TLR2, 3, 4, 5, 6, 7,8, 9, or 10 proteins are homologous to other Toll like receptorproteins, but each have structural differences. For example, a humanTLR2 gene coding sequence probably has about 70% identity with thenucleotide coding sequence of mouse TLR2. At the amino acid level, thereis also likely to be reasonable identity.

The biological activities of the TLRs will be related to addition orremoval of phosphate moieties to substrates, typically in a specificmanner, but occasionally in a non specific manner. Substrates may beidentified, or conditions for enzymatic activity may be assayed bystandard methods, e.g., as described in Hardie, et al., The ProteinKinase FactBook vols. I and II, Academic Press, San Diego, Calif.(1995); Hanks, et al., Meth. Enzymol. 200, 38 (1991); Hunter, et al.,Cell 70, 375 (1992); Lewin, Cell 61, 743 (1990); Pines, et al., ColdSpring Harbor Symp. Quant. Biol. 56, 449 (1991); and Parker, et al.,Nature 363, 736 (1993).

III. Nucleic Acids

This invention contemplates use of isolated nucleic acid or fragments,e.g., which encode these or closely related proteins, or fragmentsthereof, e.g., to encode a corresponding polypeptide, preferably onewhich is biologically active. In addition, this invention coversisolated or recombinant DNA which encodes such proteins or polypeptideshaving characteristic sequences of the respective TLRs, individually oras a group. Typically, the nucleic acid is capable of hybridizing, underappropriate conditions, with a nucleic acid sequence segment shown inSEQ ID NO: 3, 5, 7, 9, 11, 13, 15, 17, 19, 21, 23, 25, 27, 29, 31, 33,35, 36, 38, 40, 42, or 44, but preferably not with a correspondingsegment of SEQ ID NO:1. Said biologically active protein or polypeptidecan be a full length protein, or fragment, and will typically have asegment of amino acid sequence highly homologous to one shown in SEQ IDNO: 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30, 32, 34, 37, 39,41, 43, or 45. Further, this invention covers the use of isolated orrecombinant nucleic acid, or fragments thereof, which encode proteinshaving fragments which are equivalent to the TLR2-10 proteins. Theisolated nucleic acids can have the respective regulatory sequences inthe 5′ and 3′ flanks, e.g., promoters, enhancers, poly-A additionsignals, and others from the natural gene.

An “isolated” nucleic acid is a nucleic acid, e.g., an RNA, DNA, or amixed polymer, which is substantially pure, e.g., separated from othercomponents which naturally accompany a native sequence, such asribosomes, polymerases, and flanking genomic sequences from theoriginating species. The term embraces a nucleic acid sequence which hasbeen removed from its naturally occurring environment, and includesrecombinant or cloned DNA isolates, which are thereby distinguishablefrom naturally occurring compositions, and chemically synthesizedanalogs or analogs biologically synthesized by heterologous systems. Asubstantially pure molecule includes isolated forms of the molecule,either completely or substantially pure.

An isolated nucleic acid will generally be a homogeneous composition ofmolecules, but will, in some embodiments, contain heterogeneity,preferably minor. This heterogeneity is typically found at the polymerends or portions not critical to a desired biological function oractivity.

A “recombinant” nucleic acid is typically defined either by its methodof production or its structure. In reference to its method ofproduction, e.g., a product made by a process, the process is use ofrecombinant nucleic acid techniques, e.g., involving human interventionin the nucleotide sequence. Typically this intervention involves invitro manipulation, although under certain circumstances it may involvemore classical animal breeding techniques. Alternatively, it can be anucleic acid made by generating a sequence comprising fusion of twofragments which are not naturally contiguous to each other, but is meantto exclude products of nature, e.g., naturally occurring mutants asfound in their natural state. Thus, for example, products made bytransforming cells with any unnaturally occurring vector is encompassed,as are nucleic acids comprising sequence derived using any syntheticoligonucleotide process. Such a process is often done to replace a codonwith a redundant codon encoding the same or a conservative amino acid,while typically introducing or removing a restriction enzyme sequencerecognition site. Alternatively, the process is performed to jointogether nucleic acid segments of desired functions to generate a singlegenetic entity comprising a desired combination of functions not foundin the commonly available natural forms, e.g., encoding a fusionprotein. Restriction enzyme recognition sites are often the target ofsuch artificial manipulations, but other site specific targets, e.g.,promoters, DNA replication sites, regulation sequences, controlsequences, or other useful features may be incorporated by design. Asimilar concept is intended for a recombinant, e.g., fusion,polypeptide. This will include a dimeric repeat. Specifically includedare synthetic nucleic acids which, by genetic code redundancy, encodeequivalent polypeptides to fragments of TLR2-5 and fusions of sequencesfrom various different related molecules, e.g., other IL-1 receptorfamily members.

A “fragment” in a nucleic acid context is a contiguous segment of atleast about 17 nucleotides, generally at least 21 nucleotides, moregenerally at least 25 nucleotides, ordinarily at least 30 nucleotides,more ordinarily at least 35 nucleotides, often at least 39 nucleotides,more often at least 45 nucleotides, typically at least 50 nucleotides,more typically at least 55 nucleotides, usually at least 60 nucleotides,more usually at least 66 nucleotides, preferably at least 72nucleotides, more preferably at least 79 nucleotides, and inparticularly preferred embodiments will be at least 85 or morenucleotides. Typically, fragments of different genetic sequences can becompared to one another over appropriate length stretches, particularlydefined segments such as the domains described below.

A nucleic acid which codes for a TLR2-10 will be particularly useful toidentify genes, mRNA, and cDNA species which code for itself or closelyrelated proteins, as well as DNAs which code for polymorphic, allelic,or other genetic variants, e.g., from different individuals or relatedspecies. Preferred probes for such screens are those regions of theinterleukin which are conserved between different polymorphic variantsor which contain nucleotides which lack specificity, and will preferablybe full length or nearly so. In other situations, polymorphic variantspecific sequences will be more useful.

This invention further covers recombinant nucleic acid molecules andfragments having a nucleic acid sequence identical to or highlyhomologous to the isolated DNA set forth herein. In particular, thesequences will often be operably linked to DNA segments which controltranscription, translation, and DNA replication. These additionalsegments typically assist in expression of the desired nucleic acidsegment.

Homologous, or highly identical, nucleic acid sequences, when comparedto one another or Table 2-10 sequences, exhibit significant similarity.The standards for homology in nucleic acids are either measures forhomology generally used in the art by sequence comparison or based uponhybridization conditions. Comparative hybridization conditions aredescribed in greater detail below.

Substantial identity in the nucleic acid sequence comparison contextmeans either that the segments, or their complementary strands, whencompared, are identical when optimally aligned, with appropriatenucleotide insertions or deletions, in at least about 60% of thenucleotides, generally at least 66%, ordinarily at least 71%, often atleast 76%, more often at least 80%, usually at least 84%, more usuallyat least 88%, typically at least 91%, more typically at least about 93%,preferably at least about 95%, more preferably at least about 96 to 98%or more, and in particlar embodiments, as high at about 99% or more ofthe nucleotides, including, e.g., segments encoding structural domainssuch as the segments described below. Alternatively, substantialidentity will exist when the segments will hybridize under selectivehybridization conditions, to a strand or its complement, typically usinga sequence derived from Tables 2-10. Typically, selective hybridizationwill occur when there is at least about 55% homology over a stretch ofat least about 14 nucleotides, more typically at least about 65%,preferably at least about 75%, and more preferably at least about 90%.See, Kanehisa, Nucl. Acids Res. 12, 203 (1984), which is incorporatedherein by reference. The length of homology comparison, as described,may be over longer stetches, and in certain embodiments will be over astretch of at least about 17 nucleotides, generally at least about 20nucleotides, ordinarily at least about 24 nucleotides, usually at leastabout 28 nucleotides, typically at least about 32 nucleotides, moretypically at least about 40 nucleotides, preferably at least about 50nucleotides, and more preferably at least about 75 to 100 or morenucleotides.

Stringent conditions, in referring to homology in the hybridizationcontext, will be stringent combined conditions of salt, temperature,organic solvents, and other parameters typically controlled inhybridization reactions. Stringent temperature conditions will usuallyinclude temperatures in excess of about 30° C., more usually in excessof about 37° C., typically in excess of about 45° C., more typically inexcess of about 55° C., preferably in excess of about 65° C., and morepreferably in excess of about 70° C. Stringent salt conditions willordinarily be less than about 500 mM, usually less than about 400 mM,more usually less than about 300 mM, typically less than about 200 mM,preferably less than about 100 mM, and more preferably less than about80 mM, even down to less than about 20 mM. However, the combination ofparameters is much more important than the measure of any singleparameter. See, e.g., Wetmur and Davidson, J. Mol. Biol. 31, 349 (1968),which is hereby incorporated herein by reference.

Alternatively, for sequence comparison, typically one sequence acts as areference sequence, to which test sequences are compared. When using asequence comparison algorithm, test and reference sequences are inputinto a computer, subsequence coordinates are designated, if necessary,and sequence algorithm program parameters are designated. The sequencecomparison algorithm then calculates the percent sequence identity forthe test sequence(s) relative to the reference sequence, based on thedesignated program parameters.

Optical alignment of sequences for comparison can be conducted, e.g., bythe local homology algorithm of Smith and Waterman, Adv. Appl. Math. 2,482 (1981), by the homology alignment algorithm of Needlman and Wunsch,J. Mol. Biol. 48, 443 (1970), by the search for similarity method ofPearson and Lipman, Proc. Nat'l Acad. Sci. USA 85, 2444 (1988), bycomputerized implementations of these algorithms (GAP, BESTFIT, FASTA,and TFASTA in the Wisconsin Genetics Software Package, Genetics ComputerGroup, 575 Science Dr., Madison, Wis.), or by visual inspection (seegenerally Ausubel et al., supra).

One example of a useful algorithm is PILEUP. PILEUP creates a multiplesequence alignment from a group of related sequences using progressive,pairwise alignments to show relationship and percent sequence identity.It also plots a tree or dendrogram showing the clustering relationshipsused to create the alignment. PILEUP uses a simplification of theprogressive alignment method of Feng and Doolittle, J. Mol. Evol. 35,351 (1987). The method used is similar to the method described byHiggins and Sharp, CABIOS 5, 151 (1989). The program can align up to 300sequences, each of a maximum length of 5,000 nucleotides or amino acids.The multiple alignment procedure begins with the pairwise alignment ofthe two most similar sequences, producing a cluster of two alignedsequences. This cluster is then aligned to the next most relatedsequence or cluster of aligned sequences. Two clusters of sequences arealigned by a simple extension of the pairwise alignment of twoindividual sequences. The final alignment is achieved by a series ofprogressive, pairwise alignments. The program is run by designatingspecific sequences and their amino acid or nucleotide coordinates forregions of sequence comparison and by designating the programparameters. For example, a reference sequence can be compared to othertest sequences to determine the percent sequence identity relationshipusing the following parameters: default gap weight (3.00), default gaplength weight (0.10), and weighted end gaps.

Another example of algorithm that is suitable for determining percentsequence identity and sequence similarity is the BLAST algorithm, whichis described Altschul, et al., J. Mol. Biol. 215, 403 (1990). Softwarefor performing BLAST analyses is publicly available through the NationalCenter for Biotechnology Information (http:www_ncbi.nlm.nih.gov/). Thisalgorithm involves first identifying high scoring sequence pairs (HSPs)by identifying short words of length W in the query sequence, whicheither match or satisfy some positive-valued threshold score T whenaligned with a word of the same length in a database sequence. T isreferred to as the neighborhood word score threshold (Altschul, et al.,supra). These initial neighborhood word hits act as seeds for initiatingsearches to find longer HSPs containing them. The word hits are thenextended in both directions along each sequence for as far as thecumulative alignment score can be increased. Extension of the word hitsin each direction are halted when: the cumulative alignment score fallsoff by the quantity X from its maximum achieved value; the cumulativescore goes to zero or below, due to the accumulation of one or morenegative-scoring residue alignments; or the end of either sequence isreached. The BLAST algorithm parameters W, T, and X determine thesensitivity and seed of the alignment. The BLAST program uses asdefaults a wordlength (W) of 11, the BLOSUM62 scoring matrix (seeHenikoff and Henikoff, Proc. Nat'l Acad. Sci. USA 89, 10915 (1989))alignments (B) of 50, expectation (E) of 10, M=5, N=4, and a comparisonof both strands.

In addition to calculating percent sequence identity, the BLASTalgorithm also performs a statistical analysis of the similarity betweentwo sequences (see, e.g., Karlin and Altschul, Proc. Nat'l Acad. Sci.USA 90, 5873 (1993)). One measure of similarity provided by the BLASTalgorithm is the smallest sum probability (P(N)), which provides anindication of the probability by which a match between two nucleotide oramino acid sequences would occur by chance. For example, a nucleic acidis considered similar to a reference sequence if the smallest sumprobability in a comparison of the test nucleic acid to the referencenucleic acid is less than about 0.1, more preferably less than about0.01, and most preferably less than about 0.001.

A further indication that two nucleic acid sequences of polypeptides aresubstantially identical is that the polypeptide encoded by the firstnucleic acid is immunologically cross reactive with the polypeptideencoded by the second nucleic acid, as described below. Thus, apolypeptide is typically substantially identical to a secondpolypeptide, e.g., where the two peptides differ only by conservativesubstitutions. Another indication that two nucleic acid sequences aresubstantially identical is that the two molecules hybridize to eachother under stringent conditions, as described below.

The isolated DNA can be readily modified by nucleotide substitutions,nucleotide deletions, nucleotide insertions, and inversions ofnucleotide stretches. These modifications result in novel DNA sequenceswhich encode this protein or its derivatives. These modified sequencescan be used to produce mutant proteins (muteins) or to enhance theexpression of variant species. Enhanced expression may involve geneamplification, increased transcription, increased translation, and othermechanisms. Such mutant TLR-like derivatives include predetermined orsite-specific mutations of the protein or its fragments, includingsilent mutations using genetic code degeneracy. “Mutant TLR” as usedherein encompasses a polypeptide otherwise falling within the homologydefinition of the TLR as set forth above, but having an amino acidsequence which differs from that of other TLR-like proteins as found innature, whether by way of deletion, substitution, or insertion. Inparticular, “site specific mutant TLR” encompasses a protein havingsubstantial homology with a protein of Tables 2-10, and typically sharesmost of the biological activities or effects of the forms disclosedherein.

Although site specific mutation sites are predetermined, mutants neednot be site specific. Mammalian TLR mutagenesis can be achieved bymaking amino acid insertions or deletions in the gene, coupled withexpression. Substitutions, deletions, insertions, or any combinationsmay be generated to arrive at a final construct. Insertions includeamino- or carboxy-terminal fusions. Random mutagenesis can be conductedat a target codon and the expressed mammalian TLR mutants can then bescreened for the desired activity. Methods for making substitutionmutations at predetermined sites in DNA having a known sequence are wellknown in the art, e.g., by M13 primer mutagenesis. See also Sambrook, etal. (1989) and Ausubel, et al. (1987 and periodic Supplements).

The mutations in the DNA normally should not place coding sequences outof reading frames and preferably will not create complementary regionsthat could hybridize to produce secondary mRNA structure such as loopsor hairpins.

The phosphoramidite method described by Beaucage and Carruthers, Tetra.Letts. 22, 1859 (1981), will produce suitable synthetic DNA fragments. Adouble stranded fragment will often be obtained either by synthesizingthe complementary strand and annealing the strand together underappropriate conditions or by adding the complementary strand using DNApolymerase with an appropriate primer sequence.

Polymerase chain reaction (PCR) techniques can often be applied inmutagenesis. Alternatively, mutagenesis primers are commonly usedmethods for generating defined mutations at predetermined sites. See,e.g., Innis, et al., PCR Protocols: A Guide to Methods and Applications,Academic Press, San Diego, Calif. (1990); and Dieffenbach and Dveksler,PCR Primer: A Laboratory Manual, Cold Spring Harbor Press, CSH, NY(1995).

IV. Proteins and Peptides

As described above, the present invention encompasses primate TLR2-10,e.g., whose sequences are disclosed in SEQ ID NO: 4, 6, 8, 10, 12, 14,16, 18, 20, 22, 24, 26, 28, 30, 32, 34, 37, 39, 41, 43, or 45, anddescribed above. Allelic and other variants are also contemplated,including, e.g., fusion proteins combining portions of such sequenceswith others, including epitope tags and functional domains.

The present invention also provides recombinant proteins, e.g.,heterologous fusion proteins using segments from these rodent proteins.A heterologous fusion protein is a fusion of proteins or segments whichare naturally not normally fused in the same manner. Thus, the fusionproduct of a TLR with an IL-1 receptor is a continuous protein moleculehaving sequences fused in a typical peptide linkage, typically made as asingle translation product and exhibiting properties, e.g., sequence orantigenicity, derived from each source peptide. A similar conceptapplies to heterologous nucleic acid sequences.

In addition, new constructs may be made from combining similarfunctional or structural domains from other related proteins, e.g., IL-1receptors or other TLRs, including species variants. For example,ligand-binding or other segments may be “swapped” between different newfusion polypeptides or fragments. See, e.g., Cunningham, et al., Science243, 1330 (1989); and O'Dowd, et al., J. Biol. Chem. 263,15985 (1988),each of which is incorporated herein by reference. Thus, new chimericpolypeptides exhibiting new combinations of specificities will resultfrom the functional linkage of receptor-binding specificities. Forexample, the ligand binding domains from other related receptormolecules may be added or substituted for other domains of this orrelated proteins. The resulting protein will often have hybrid functionand properties. For example, a fusion protein may include a targetingdomain which may serve to provide sequestering of the fusion protein toa particular subcellular organelle.

Candidate fusion partners and sequences can be selected from varioussequence data bases, e.g., GenBank, c/o IntelliGenetics, Mountain View,Calif.; and BCG, University of Wisconsin Biotechnology Computing Group,Madison, Wis., which are each incorporated herein by reference.

The present invention particularly provides muteins which bind Tollligands, and/or which are affected in signal transduction. Structuralalignment of human TLR1-10 with other members of the IL-1 family showconserved features/residues. See, e.g., FIG. 3A. Alignment of the humanTLR sequences with other members of the IL-1 family indicates variousstructural and functionally shared features. See also, Bazan, et al.,Nature 379, 591 (1996); Lodi, et al., Science 263, 1762 (1994); Sayleand Milner-White, TIBS 20, 374 (1995); and Gronenberg, et al., ProteinEngineering 4, 263 (1991).

The IL-1α and IL-1β ligands bind an IL-1 receptor type I as the primaryreceptor and this complex then forms a high affinity receptor complexwith the IL-1 receptor type III. Such receptor subunits are probablyshared with the new IL-1 family members.

Similar variations in other species counterparts of TLR2-10 sequences,e.g., in the corresponding regions, should provide similar interactionswith ligand or substrate. Substitutions with either mouse sequences orhuman sequences are particularly preferred. Conversely, conservativesubstitutions away from the ligand binding interaction regions willprobably preserve most signaling activities.

“Derivatives” of the primate TLR2-10 include amino acid sequencemutants, glycosylation variants, metabolic derivatives and covalent oraggregative conjugates with other chemical moieties. Covalentderivatives can be prepared by linkage of functionalities to groupswhich are found in the TLR amino acid side chains or at the N— orC-terminal, e.g., by means which are well known in the art. Thesederivatives can include, without limitation, aliphatic esters or amidesof the carboxyl terminus, or of residues containing carboxyl sidechains, O-acyl derivatives of hydroxyl group-containing residues, andN-acyl derivatives of the amino terminal amino acid or amino-groupcontaining residues, e.g., lysine or arginine. Acyl groups are selectedfrom the group of alkyl-moieties including C3 to C18 normal alkyl,thereby forming alkanoyl aroyl species.

In particular, glycosylation alterations are included, e.g., made bymodifying the glycosylation patterns of a polypeptide during itssynthesis and processing, or in further processing steps. Particularlypreferred means for accomplishing this are by exposing the polypeptideto glycosylating enzymes derived from cells which normally provide suchprocessing, e.g., mammalian glycosylation enzymes. Deglycosylationenzymes are also contemplated. Also embraced are versions of the sameprimary amino acid sequence which have other minor modifications,including phosphorylated amino acid residues, e.g., phosphotyrosine,phosphoserine, or phosphothreonine.

A major group of derivatives are covalent conjugates of the receptors orfragments thereof with other proteins of polypeptides. These derivativescan be synthesized in recombinant culture such as N— or C-terminalfusions or by the use of agents known in the art for their usefulness incross-linking proteins through reactive side groups. Preferredderivatization sites with cross-linking agents are at free amino groups,carbohydrate moieties, and cysteine residues.

Fusion polypeptides between the receptors and other homologous orheterologous proteins are also provided. Homologous polypeptides may befusions between different receptors, resulting in, for instance, ahybrid protein exhibiting binding specificity for multiple differentToll ligands, or a receptor which may have broadened or weakenedspecificity of substrate effect. Likewise, heterologous fusions may beconstructed which would exhibit a combination of properties oractivities of the derivative proteins. Typical examples are fusions of areporter polypeptide, e.g., luciferase, with a segment or domain of areceptor, e.g., a ligand-binding segment, so that the presence orlocation of a desired ligand may be easily determined. See, e.g., Dull,et al., U.S. Pat. No. 4,859,609, which is hereby incorporated herein byreference. Other gene fusion partners include glutathione-S-transferase(GST), bacterial β-galactosidase, trpE, Protein A, β-lactamase, alphaamylase, alcohol dehydrogenase, and yeast alpha mating factor. See,e.g., Godowski, et al., Science 241, 812 (1988).

Such polypeptides may also have amino acid residues which have beenchemically modified by phosphorylation, sulfonation, biotinylation, orthe addition or removal of other moieties, particularly those which havemolecular shapes similar to phosphate groups. In some embodiments, themodifications will be useful labeling reagents, or serve as purificationtargets, e.g., affinity ligands.

Fusion proteins will typically be made by either recombinant nucleicacid methods or by synthetic polypeptide methods. Techniques for nucleicacid manipulation and expression are described generally, for example,in Sambrook, et al., Molecular Cloning: A Laboratory Manual (2d ed.),Vols. 1-3, Cold Spring Harbor Laboratory (1989), and Ausubel, et al.,Current Protocols in Molecular Biology, Greene/Wiley, New York (1987),which are each incorporated herein by reference. Techniques forsynthesis of polypeptides are described, for example, in Merrifield, J.Amer. Chem. Soc. 85, 2149 (1963); Merrifield, Science 232, 341 (1986);and Atherton, et al., Solid Phase Peptide Synthesis: A PracticalApproach, IRL Press, Oxford (1989); each of which is incorporated hereinby reference. See also Dawson, et al., Science 266,776 (1994) formethods to make larger polypeptides.

This invention also contemplates the use of derivatives of a TLR2-10other than variations in amino acid sequence or glycosylation. Suchderivatives may involve covalent or aggregative association withchemical moieties. These derivatives generally fall into three classes:(1) salts, (2) side chain and terminal residue covalent modifications,and (3) adsorption complexes, for example with cell membranes. Suchcovalent or aggregative derivatives are useful as immunogens, asreagents in immunoassays, or in purification methods such as foraffinity purification of a receptor or other binding molecule, e.g., anantibody. For example, a Toll ligand can be immobilized by covalentbonding to a solid support such as cyanogen bromide-activated Sepharose,by methods which are well known in the art, or adsorbed onto polyolefinsurfaces, with or without glutaraldehyde cross-linking, for use in theassay or purification of a TLR receptor, antibodies, or other similarmolecules. The ligand can also be labeled with a detectable group, forexample radioiodinated by the chloramine T procedure, covalently boundto rare earth chelates, or conjugated to another fluorescent moiety foruse in diagnostic assays.

Soluble Toll-like receptors (sTLR) as used in the context of the presentinvention refers to a protein, or a substantially equivalent analog,having an amino acid sequence corresponding to the extracellular regionof native TLR2, TLR3, TLR4, TLR5, TLR6, TLR7, TLR8, TLR9, or TLR10.Soluble TLRs may be constructed by deleting terminal or internalresidues or sequences. Particularly preferred sequences include those inwhich the transmembrane region and intracellular domain of a TLR aredeleted or substituted with hydrophilic residues to facilitate secretionof the receptor into the cell culture medium. Software programs can beused for predicting the transmembrane, extracellular, and cytosolicdomains of a polypeptide. These software programs can be found in theGCG WISCONSIN PACKAGE (Accelrys, Inc., San Diego, Calif.) and in theLASERGENE sequence analysis software (DNAStar, Inc., Madison, Wis.). Theresulting water-soluble protein is referred to as a soluble TLRmolecule, where this TLR retains its ability to bind its ligand, e.g.,bacterial lipopolysaccharide, endotoxin, peptidoglycan, lipoteichoicacid, and unmethylated CpG oligonucleotides.

When administered in therapeutic formulations, soluble TLRs circulate inthe body and bind to its ligand or ligands, where the ligands may besoluble, intracellular, intercellular, or occurring as part of a microbeor fungus. When the soluble TLR binds to the ligand, the ligand isprevented from interacting with its natural TLR, and thereby preventedfrom relaying a signal to the cell.

DNA constructs coding for soluble TLRs can be inserted in appropriateexpression vectors, expressed in cultured cells or microorganisms, andexpressed. The expressed soluble TLR can be assayed for the ability tobind the above mentioned ligands (See, e.g., U.S. Pat. No. 5,767,065,issued to Mosley, et al.; U.S. Pat. No. 5,712,155, issued to Smith, etal.)

V. Making Nucleic Acids and Protein

DNA which encodes the protein or fragments thereof can be obtained bychemical synthesis, screening cDNA libraries, or by screening genomiclibraries prepared from a wide variety of cell lines or tissue samples.Natural sequences can be isolated using standard methods and thesequences provided herein, e.g., in Tables 2-10. Other speciescounterparts can be identified by hybridization techniques, or byvarious PCR techniques, combined with or by searching in sequencedatabases, e.g., GenBank.

This DNA can be expressed in a wide variety of host cells for thesynthesis of a full-length receptor or fragments which can in turn, forexample, be used to generate polyclonal or monoclonal antibodies; forbinding studies; for construction and expression of modified ligandbinding or kinase/phosphatase domains; and for structure/functionstudies. Variants or fragments can be expressed in host cells that aretransformed or transfected with appropriate expression vectors. Thesemolecules can be substantially free of protein or cellular contaminants,other than those derived from the recombinant host, and therefore areparticularly useful in pharmaceutical compositions when combined with apharmaceutically acceptable carrier and/or diluent. The protein, orportions thereof, may be expressed as fusions with other proteins.

Expression vectors are typically self-replicating DNA or RNA constructscontaining the desired receptor gene or its fragments, usually operablylinked to suitable genetic control elements that are recognized in asuitable host cell. These control elements are capable of effectingexpression within a suitable host. The specific type of control elementsnecessary to effect expression will depend upon the eventual host cellused. Generally, the genetic control elements can include a prokaryoticpromoter system or a eukaryotic promoter expression control system, andtypically include a transcriptional promoter, an optional operator tocontrol the onset of transcription, transcription enhancers to elevatethe level of mRNA expression, a sequence that encodes a suitableribosome binding site, and sequences that terminate transcription andtranslation. Expression vectors also usually contain an origin ofreplication that allows the vector to replicate independently of thehost cell.

The vectors of this invention include those which contain DNA whichencodes a protein, as described, or a fragment thereof encoding abiologically active equivalent polypeptide. The DNA can be under thecontrol of a viral promoter and can encode a selection marker. Thisinvention further contemplates use of such expression vectors which arecapable of expressing eukaryotic cDNA coding for such a protein in aprokaryotic or eukaryotic host, where the vector is compatible with thehost and where the eukaryotic cDNA coding for the receptor is insertedinto the vector such that growth of the host-containing the vectorexpresses the cDNA in question. Usually, expression vectors are designedfor stable replication in their host cells or for amplification togreatly increase the total number of copies of the desirable gene percell. It is not always necessary to require that an expression vectorreplicate in a host cell, e.g., it is possible to effect transientexpression of the protein or its fragments in various hosts usingvectors that do not contain a replication origin that is recognized bythe host cell. It is also possible to use vectors that cause integrationof the protein encoding portion or its fragments into the host DNA byrecombination.

Vectors, as used herein, comprise plasmids, viruses, bacteriophage,integratable DNA fragments, and other vehicles which enable theintegration of DNA fragments into the genome of the host. Expressionvectors are specialized vectors which contain genetic control elementsthat effect expression of operably linked genes. Plasmids are the mostcommonly used form of vector but all other forms of vectors which servean equivalent function and which are, or become, known in the art aresuitable for use herein. See, e.g., Pouwels, et al., Cloning Vectors: ALaboratory Manual, Elsevier, N.Y. (1985), and Rodriquez, et al. (eds.)Vectors: A Survey of Molecular Cloning Vectors and Their Uses,Buttersworth, Boston (1988), which are incorporated herein by reference.

Transformed cells are cells, preferably mammalian, that have beentransformed or transfected with receptor vectors constructed usingrecombinant DNA techniques. Transformed host cells usually express thedesired protein or its fragments, but for purposes of cloning,amplifying, and manipulating its DNA, do not need to express the subjectprotein. This invention further contemplates culturing transformed cellsin a nutrient medium, thus permitting the receptor to accumulate in thecell membrane. The protein can be recovered, either from the culture or,in certain instances, from the culture medium.

For purposes of this invention, nucleic sequences are operably linkedwhen they are functionally related to each other. For example, DNA for apresequence or secretory leader is operably linked to a polypeptide ifit is expressed as a preprotein or participates in directing thepolypeptide to the cell membrane or in secretion of the polypeptide. Apromoter is operably linked to a coding sequence if it controls thetranscription of the polypeptide; a ribosome binding site is operablylinked to a coding sequence if it is positioned to permit translation.Usually, operably linked means contiguous and in reading frame, however,certain genetic elements such as repressor genes are not contiguouslylinked but still bind to operator sequences that in turn controlexpression.

Suitable host cells include prokaryotes, lower eukaryotes, and highereukaryotes. Prokaryotes include both gram negative and gram positiveorganisms, e.g., E. coli and B. subtilis. Lower eukaryotes includeyeasts, e.g., S. cerevisiae and Pichia, and species of the genusDictyostelium. Higher eukaryotes include established tissue culture celllines from animal cells, both of non-mammalian origin, e.g., insectcells, and birds, and of mammalian origin, e.g., human, primates, androdents.

Prokaryotic host-vector systems include a wide variety of vectors formany different species. As used herein, E. coli and its vectors will beused generically to include equivalent vectors used in otherprokaryotes. A representative vector for amplifying DNA is pBR322 ormany of its derivatives. Vectors that can be used to express thereceptor or its fragments include, but are not limited to, such vectorsas those containing the lac promoter (pUC-series); trp promoter(pBR322-trp); Ipp promoter (the pIN-series); lambda-pP or pR promoters(pOTS); or hybrid promoters such as ptac (pDR540). See Brosius, et al.,“Expression Vectors Employing Lambda-, trp-, lac-, and Ipp-derivedPromoters”, in Vectors: A Survey of Molecular Cloning Vectors and TheirUses, (eds. Rodriguez and Denhardt), Buttersworth, Boston, Chapter 10,pp. 205-236 (1988), which is incorporated herein by reference.

Lower eukaryotes, e.g., yeasts and Dictyostelium, may be transformedwith TLR sequence containing vectors. For purposes of this invention,the most common lower eukaryotic host is the baker's yeast,Saccharomyces cerevisiae. It will be used to generically represent lowereukaryotes although a number of other strains and species are alsoavailable. Yeast vectors typically consist of a replication origin(unless of the integrating type), a selection gene, a promoter, DNAencoding the receptor or its fragments, and sequences for translationtermination, polyadenylation, and transcription termination. Suitableexpression vectors for yeast include such constitutive promoters as3-phosphoglycerate kinase and various other glycolytic enzyme genepromoters or such inducible promoters as the alcohol dehydrogenase 2promoter or metallothionine promoter. Suitable vectors includederivatives of the following types: self-replicating low copy number(such as the YRp-series), self-replicating high copy number (such as theYEp-series); integrating types (such as the YIp-series), ormini-chromosomes (such as the YCp-series).

Higher eukaryotic tissue culture cells are normally the preferred hostcells for expression of the functionally active interleukin protein. Inprinciple, any higher eukaryotic tissue culture cell line is workable,e.g., insect baculovirus expression systems, whether from aninvertebrate or vertebrate source. However, mammalian cells arepreferred. Transformation or transfection and propagation of such cellshas become a routine procedure. Examples of useful cell lines includeHeLa cells, Chinese hamster ovary (CHO) cell lines, baby rat kidney(BRK) cell lines, insect cell lines, bird cell lines, and monkey (COS)cell lines. Expression vectors for such cell lines usually include anorigin of replication, a promoter, a translation initiation site, RNAsplice sites (if genomic DNA is used), a polyadenylation site, and atranscription termination site. These vectors also usually contain aselection gene or amplification gene. Suitable expression vectors may beplasmids, viruses, or retroviruses carrying promoters derived, e.g.,from such sources as from adenovirus, SV40, parvoviruses, vacciniavirus, or cytomegalovirus. Representative examples of suitableexpression vectors include pCDNA1; pCD, see Okayama, et al., Mol. CellBiol. 5, 1136 (1985); pMC1neo PolyA, see Thomas, et al., Cell 51, 503(1987); and a baculovirus vector such as pAC 373 or pAC 610.

For secreted proteins, an open reading frame usually encodes apolypeptide that consists of a mature or secreted product covalentlylinked at its N-terminus to a signal peptide. The signal peptide iscleaved prior to secretion of the mature, or active, polypeptide. Thecleavage site can be predicted with a high degree of accuracy fromempirical rules, e.g., von-Heijne, Nucleic Acids Research 14, 4683(1986), and the precise amino acid composition of the signal peptidedoes not appear to be critical to its function, e.g., Randall, et al.,Science 243, 1156 (1989); Kaiser, et al., Science 235, 312 (1987).

It will often be desired to express these polypeptides in a system whichprovides a specific or defined glycosylation pattern. In this case, theusual pattern will be that provided naturally by the expression system.However, the pattern will be modifiable by exposing the polypeptide,e.g., an unglycosylated form, to appropriate glycosylating proteinsintroduced into a heterologous expression system. For example, thereceptor gene may be co-transformed with one or more genes encodingmammalian or other glycosylating enzymes. Using this approach, certainmammalian glycosylation patterns will be achievable in prokaryote orother cells.

The source of TLR can be a eukaryotic or prokaryotic host expressingrecombinant TLR, such as is described above. The source can also be acell line such as mouse Swiss 3T3 fibroblasts, but other mammalian celllines are also contemplated by this invention, with the preferred cellline being from the human species.

Now that the sequences are known, the primate TLRs, fragments, orderivatives thereof can be prepared by conventional processes forsynthesizing peptides. These include processes such as are described inStewart and Young, Solid Phase Peptide Synthesis, Pierce Chemical Co.,Rockford, Ill. (1984); Bodanszky and Bodanszky, The Practice of PeptideSynthesis, Springer-Verlag, New York; and Bodanszky (1984) ThePrinciples of Peptide Synthesis, Springer-Verlag, New York; all of eachwhich are incorporated herein by reference. For example, an azideprocess, an acid chloride process, an acid anhydride process, a mixedanhydride process, an active ester process (e.g., p-nitrophenyl ester,N-hydroxysuccinimide ester, or cyanomethyl ester), a carbodiimidazoleprocess, an oxidative-reductive process, or a dicyclohexylcarbodiimide(DCCD)/additive process can be used. Solid phase and solution phasesyntheses are both applicable to the foregoing processes. Similartechniques can be used with partial TLR sequences.

The TLR proteins, fragments, or derivatives are suitably prepared inaccordance with the above processes as typically employed in peptidesynthesis, generally either by a so-called stepwise process whichcomprises condensing an amino acid to the terminal amino acid, one byone in sequence, or by coupling peptide fragments to the terminal aminoacid. Amino groups that are not being used in the coupling reactiontypically must be protected to prevent coupling at an incorrectlocation.

If a solid phase synthesis is adopted, the C-terminal amino acid isbound to an insoluble carrier or support through its carboxyl group. Theinsoluble carrier is not particularly limited as long as it has abinding capability to a reactive carboxyl group. Examples of suchinsoluble carriers include halomethyl resins, such as chloromethyl resinor bromomethyl resin, hydroxymethyl resins, phenol resins,tert-alkyloxycarbonylhydrazidated resins, and the like.

An amino group-protected amino acid is bound in sequence throughcondensation of its activated carboxyl group and the reactive aminogroup of the previously formed peptide or chain, to synthesize thepeptide step by step. After synthesizing the complete sequence, thepeptide is split off from the insoluble carrier to produce the peptide.This solid-phase approach is generally described by Merrifield, et al.,J. Am. Chem. Soc. 85, 2149 (1963), which is incorporated herein byreference.

The prepared protein and fragments thereof can be isolated and purifiedfrom the reaction mixture by means of peptide separation, for example,by extraction, precipitation, electrophoresis, various forms ofchromatography, and the like. The receptors of this invention can beobtained in varying degrees of purity depending upon desired uses.Purification can be accomplished by use of the protein purificationtechniques disclosed herein, see below, or by the use of the antibodiesherein described in methods of immunoabsorbant affinity chromatography.This immunoabsorbant affinity chromatography is carried out by firstlinking the antibodies to a solid support and then contacting the linkedantibodies with solubilized lysates of appropriate cells, lysates ofother cells expressing the receptor, or lysates or supernatants of cellsproducing the protein as a result of DNA techniques, see below.

Generally, the purified protein will be at least about 40% pure,ordinarily at least about 50% pure, usually at least about 60% pure,typically at least about 70% pure, more typically at least about 80%pure, preferable at least about 90% pure and more preferably at leastabout 95% pure, and in particular embodiments, 97%-99% or more. Puritywill usually be on a weight basis, but can also be on a molar basis.Different assays will be applied as appropriate.

The present invention further relates to variants of the nucleic acidmolecules of the present invention, which encode portions, analogs orderivatives of a TLR, and to variants of a TLR polypeptide. Variants mayoccur naturally, such as a natural allelic variant. By an “allelicvariant” is intended one of several alternate forms of a gene occupyinga given locus on a chromosome of an organism (Lewin, Genes II, JohnWiley and Sons, New York (1985)). Non-naturally occurring variants maybe produced using art-known mutagenesis techniques. Such variantsinclude those produced by nucleotide substitutions, deletions oradditions. The substitutions, deletions or additions may involve one ormore nucleotides. The variants may be altered in coding regions,non-coding regions, or both. Alterations in the coding regions mayproduce conservative or non-conservative amino acid substitutions,deletions or additions. Some contemplated examples of conservativesubstitutions include substitution of a hydrophobic residue such asisoleucine, valine, leucine or methionine for another hydrophobicresidue. Also, a polar residue such as arginine, lysine, glutamic acid,aspartic acid, glutamine, asparagine, and the like, can beconservatively substituted for another member of this group. Stillanother aspect of a polypeptide incorporating conservative substitutionsoccurs when a substituted amino acid residue replaces an unsubstitutedparent amino acid residue. The variations may include silentsubstitutions, additions and deletions, which do not alter theproperties and activities of the TLR or portions thereof.

VI. Antibodies

The term “antibody” is used in the broadest sense and specificallycovers monoclonal antibodies, antibody compositions with polyepitopicspecificity, bispecific antibodies, and single-chain molecules, as wellas antibody fragments (e.g., Fab, F(ab′)₂, and Fv), so long as theyantagonize the biological activity of TLR2, TLR3, TLR4, TLR5, TLR6,TLR7, TLR8, TLR9, or TLR10.

The term “monoclonal antibody” as used herein refers to an antibodyobtained from a population of substantially homogeneous antibodies,i.e., the individual antibodies comprising the population are identicalexcept for possible naturally occurring mutations that may be present inminor amounts. Monoclonal antibodies are highly specific, being directedagainst a single antigenic site. Furthermore, in contrast toconventional (polyclonal) antibody preparations which typically includedifferent antibodies directed against different determinants (epitopes),each monoclonal antibody is directed against a single determinant on theantigen. In addition to their specificity, the monoclonal antibodies areadvantageous in that they are synthesized by the hybridoma culture,uncontaminated by other immunoglobulins. The modifier “monoclonal”indicates the character of the antibody as being obtained from asubstantially homogeneous population of antibodies, and is not to beconstrued as requiring production of the antibody by any particularmethod. For example, the monoclonal antibodies to be used in accordancewith the present invention may be made by the hybridoma method firstdescribed by Kohler et al., Nature, 256: 495 (1975), or may be made byrecombinant DNA methods (see, e.g., U.S. Pat. No. 4,816,567). The“monoclonal antibodies” may also be isolated from phage antibodylibraries using the techniques described in Clackson et al., Nature,352, 624(1991) and Marks et al., J. Mol. Biol., 222, 581(1991), forexample.

Monoclonal antibodies include “chimeric” antibodies (immunoglobulins) inwhich a portion of the heavy and/or light chain is identical with orhomologous to corresponding sequences in antibodies derived from aparticular species or belonging to a particular antibody class orsubclass, while the remainder of the chain(s) is identical with orhomologous to corresponding sequences in antibodies derived from anotherspecies or belonging to another antibody class or subclass, as well asfragments of such antibodies, so long as they exhibit the desiredbiological activity (U.S. Pat. No. 4,816,567; Morrison et al., Proc.Natl. Acad. Sci. USA, 81, 6851(1984)).

“Humanized” forms of non-human (e.g., murine) antibodies are chimericimmunoglobulins, immunoglobulin chains or fragments thereof (such as Fv,Fab, Fab′, F(ab′)₂ or other antigen-binding subsequences of antibodies)which contain minimal sequence derived from non-human immunoglobulin.For the most part, humanized antibodies are human immunoglobulins(recipient antibody) in which residues from a complementary-determiningregion (CDR) of the recipient are replaced by residues from a CDR of anon-human species (donor antibody) such as mouse, rat or rabbit havingthe desired specificity, affinity, and capacity. In some instances, Fvframework region (FR) residues of the human immunoglobulin are replacedby corresponding non-human residues. Furthermore, humanized antibodiesmay comprise residues which are found neither in the recipient antibodynor in the imported CDR or framework sequences. These modifications aremade to further refine and optimize antibody performance. In general,the humanized antibody will comprise substantially all of at least one,and typically two, variable domains, in which all or substantially allof the CDR regions correspond to those of a non-human immunoglobulin andall or substantially all of the FR regions are those of a humanimmunoglobulin sequence. The humanized antibody optimally also willcomprise at least a portion of an immunoglobulin constant region (Fc),typically that of a human immunoglobulin. For further details, see Joneset al., Nature, 321, 522 (1986); Reichmann et al., Nature, 332,323(1988); and Presta, Curr. Op. Struct. Biol., 2, 593 (1992). Thehumanized antibody includes a Primatized.™ antibody wherein theantigen-binding region of the antibody is derived from an antibodyproduced by immunizing macaque monkeys with the antigen of interest.

“Single-chain Fv” or “sFv” antibody fragments comprise the V_(H) andV_(L) domains of antibody, wherein these domains are present in a singlepolypeptide chain. Generally, the Fv polypeptide further comprises apolypeptide linker between the V_(H) and V_(L) domains which enables thesFv to form the desired structure for antigen binding. For a review ofsFv see Pluckthun in The Pharmacology of Monoclonal Antibodies, vol.113, Rosenburg and Moore eds., Springer-Verlag, New York, pp.269-315(1994).

Antibodies can be raised to the various TLR proteins and fragmentsthereof, both in naturally occurring native forms and in theirrecombinant forms, the difference being that antibodies to the activereceptor are more likely to recognize epitopes which are only present inthe native conformations. Denatured antigen detection can also be usefulin, e.g., Western analysis.

A TLR of this invention can be used as an immunogen for the productionof antisera or antibodies specific, e.g., capable of distinguishingbetween various Toll-like receptors or various fragments thereof. Thepurified TLR can be used to screen monoclonal antibodies orantigen-binding fragments prepared by immunization with various forms ofimpure preparations containing the protein.

The purified TLR can also be used as a reagent to detect antibodiesgenerated in response to the presence of elevated levels of expression,or immunological disorders which lead to antibody production to theendogenous receptor.

Additionally, TLR fragments may also serve as immunogens to produce theantibodies of the present invention, as described immediately below. Forexample, this invention contemplates antibodies having binding affinityto or being raised against the amino acid sequences shown in SEQ ID NOS:4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30, 32, 34, 37, 39, 41,43, or 45, fragments thereof, or various homologous peptides. Inparticular, this invention contemplates antibodies having bindingaffinity to, or having been raised against, specific fragments which arepredicted to be, or actually are, exposed at the exterior proteinsurface of the native TLR.

The blocking of physiological response to the receptor ligands mayresult from the inhibition of binding of the ligand to the receptor,likely through competitive inhibition. Thus, in vitro assays of thepresent invention will often use antibodies or antigen binding segmentsof these antibodies, or fragments attached to solid phase substrates.These assays will also allow for the diagnostic determination of theeffects of either ligand binding region mutations and modifications, orother mutations and modifications, e.g., which affect signaling orenzymatic function.

This invention also contemplates the use of competitive drug screeningassays, e.g., where antibodies to the receptor (or antibody fragments)compete with a test compound for binding to a ligand or other antibody.The invention also contemplates use of water-soluble versions of theToll-like receptors for drug screening. In this manner, the neutralizingantibodies or fragments can be used to detect the presence of apolypeptide which shares one or more binding sites to a receptor and canalso be used to occupy binding sites on a receptor that might otherwisebind a ligand.

Preferred antibodies will exhibit properties of both affinity andselectivity. High affinity is generally preferred, while selectivitywill allow distinction between various embodiment subsets. Inparticular, it will be desirable to possess antibody preparationscharacterized to bind, e.g., various specific combinations of relatedmembers while not binding others. Such various combinatorial subsets arespecifically enabled, e.g., these reagents may be generated or selectedusing standard methods of immunoaffinity, selection, etc.

Antibodies, including binding fragments and single chain versions,against predetermined fragments of the protein can be raised byimmunization of animals with conjugates of the fragments withimmunogenic proteins. Monoclonal antibodies are prepared from cellssecreting the desired antibody. These antibodies can be screened forbinding to normal or detective protein, or screened for agonistic orantagonistic activity. These monoclonal antibodies will usually bindwith at least a K_(D) of about 1 mM, more usually at least about 300 μM,typically at least about 100 μM, more typically at least about 30 μM,preferably at least about 10 μM, and more preferably at least about 3 μMor better.

The antibodies, including antigen binding fragments, of this inventioncan have significant diagnostic or therapeutic value. They can be potentantagonists that bind to the receptor and inhibit binding to ligand orinhibit the ability of the receptor to elicit a biological response,e.g., act on its substrate. They can also be agonists that bind to thereceptor, and initiate signals that are similar to those stimulated tothe receptor's ligand under physiological conditions. Antibodies to aToll-like receptor can also be coupled to toxins or radionuclides toproduce a conjugate, where the conjugate can be used for inhibiting orkilling cells bearing a Toll-like receptor. Further, these antibodiescan be conjugated to drugs or other therapeutic agents, either directlyor indirectly by means of a linker.

The antibodies of this invention can also be useful in diagnosticapplications. As capture or non-neutralizing antibodies, they might bindto the receptor without inhibiting ligand or substrate binding. Asneutralizing antibodies, they can be useful in competitive bindingassays. They will also be useful in detecting or quantifying ligand.They may be used as reagents for Western blot analysis, or forimmunoprecipitation or immunopurification of the respective protein.

Protein fragments may be joined to other materials, particularlypolypeptides, as fused or covalently joined polypeptides to be used asimmunogens. Mammalian TLR and its fragments may be fused or covalentlylinked to a variety of immunogens, such as keyhole limpet hemocyanin,bovine serum albumin, tetanus toxoid, etc. See Microbiology, HoeberMedical Division, Harper and Row, (1969); Landsteiner, Specificity ofSerological Reactions, Dover Publications, New York (1962); andWilliams, et al., Methods in Immunology and Immunochemistry, Vol. 1,Academic Press, New York (1967); each of which are incorporated hereinby reference, for descriptions of methods of preparing polyclonalantisera. A typical method involves hyperimmunization of an animal withan antigen. The blood of the animal is then collected shortly after therepeated immunizations and the gamma globulin is isolated.

In some instances, it is desirable to prepare monoclonal antibodies fromvarious mammalian hosts, such as mice, rodents, primates, humans, etc.Description of techniques for preparing such monoclonal antibodies maybe found in, e.g., Stites, et al. (eds.), Basic and Clinical Immunology(4th ed.), Lange Medical Publications, Los Altos, Calif., and referencescited therein; Harlow and Lane (1988) Antibodies: A Laboratory Manual,CSH Press; Goding, Monoclonal Antibodies: Principles and Practice (2ded) Academic Press, New York (1986); and particularly in Kohler andMilstein, Nature 256, 495 (1975), which discusses one method ofgenerating monoclonal antibodies. Each of these references isincorporated herein by reference. Summarized briefly, this methodinvolves injecting an animal with an immunogen. The animal is thensacrificed and cells taken from its spleen, which are then fused withmyeloma cells. The result is a hybrid cell or “hybridoma” that iscapable of reproducing in vitro. The population of hybridomas is thenscreened to isolate individual clones, each of which secrete a singleantibody species to the immunogen. In this manner, the individualantibody species obtained are the products of immortalized and clonedsingle B cells from the immune animal generated in response to aspecific site recognized on the immunogenic substance.

Other suitable techniques involve in vitro exposure of lymphocytes tothe antigenic polypeptides or alternatively to selection of libraries ofantibodies in phage or similar vectors. See, Huse, et al., Science 246,1275 (1989); and Ward, et al., Nature 341, 544 (1989), each of which ishereby incorporate herein by reference. The polypeptides and antibodiesof the present invention may be used with or without modification,including chimeric or humanized antibodies. Frequently, the polypeptidesand antibodies will be labeled by joining, either covalently ornon-covalently, a substance which provides for a detectable signal. Awide variety of labels and conjugation techniques are known and arereported extensively in both the scientific and patent literature.Suitable labels include radionuclides, enzymes, substrates, cofactors,inhibitors, fluorescent moieties, chemiluminescent moieties, magneticparticles, and the like. Patents, teaching the use of such labelsinclude U.S. Pat. Nos. 3,817,837; 3,850,752; 3,939,350; 3,996,345;4,277,437; 4,275,149; and 4,366,241. Also, recombinant or chimericimmunoglobulins may be produced, see Cabilly, U.S. Pat. No. 4,816,567;or made in transgenic mice, see Mendez, et al., Nature Genetics 15, 146(1997). These references are incorporated herein by reference.

The antibodies of this invention can also be used for affinitychromatography in isolating the TLRs. Columns can be prepared where theantibodies are linked to a solid support, e.g., particles, such asAGAROSE, SEPHADEX, or the like, where a cell lysate may be passedthrough the column, the column washed, followed by increasingconcentrations of a mild denaturant, whereby the purified protein willbe released. The protein may be used to purify antibody.

The antibodies may also be used to screen expression libraries forparticular expression products. Usually the antibodies used in such aprocedure will be labeled with a moiety allowing easy detection ofpresence of antigen by antibody binding.

Antibodies raised against a TLR will also be used to raiseanti-idiotypic antibodies. These will be useful in detecting ordiagnosing various immunological conditions related to expression of theprotein or cells which express the protein. They also will be useful asagonists or antagonists of the ligand, which may be competitiveinhibitors or substitutes for naturally occurring ligands.

A TLR protein that specifically binds to or that is specificallyimmunoreactive with an antibody generated against a defined immunogen,such as an immunogen consisting of the amino acid sequence of SEQ ID NO:4, 6, 8, 10, 12, 14, 16, 18, 20, 22, or 24, is typically determined inan immunoassay. The immunoassay typically uses a polyclonal antiserumwhich was raised, e.g., to a protein of SEQ ID NO: 4, 6, 8, 10, 12, 14,16, 18, 20, 22, or 24. This antiserum is selected to have lowcrossreactivity against other IL-1R family members, e.g., TLR1,preferably from the same species, and any such crossreactivity isremoved by immunoabsorption prior to use in the immunoassay.

In order to produce antisera for use in an immunoassay, the protein ofSEQ ID NO: 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, or 24, or a combinationthereof, is isolated as described herein. For example, recombinantprotein may be produced in a mammalian cell line. An appropriate host,e.g., an inbred strain of mice such as Balb/c, is immunized with theselected protein, typically using a standard adjuvant, such as Freund'sadjuvant, and a standard mouse immunization protocol (see Harlow andLane, supra). Alternatively, a synthetic peptide derived from thesequences disclosed herein and conjugated to a carrier protein can beused an immunogen. Polyclonal sera are collected and titered against theimmunogen protein in an immunoassay, e.g., a solid phase immunoassaywith the immunogen immobilized on a solid support. Polyclonal antiserawith a titer of 10⁴ or greater are selected and tested for their crossreactivity against other IL-1R family members, e.g., mouse TLRs or humanTLR1, using a competitive binding immunoassay such as the one describedin Harlow and Lane, supra, at pages 570-573. Preferably at least two TLRfamily members are used in this determination in conjunction with eitheror some of the human TLR2-10. These IL-1R family members can be producedas recombinant proteins and isolated using standard molecular biologyand protein chemistry techniques as described herein.

Immunoassays in the competitive binding format can be used for thecrossreactivity determinations. For example, the proteins of SEQ ID NO:4, 6, 8, 10, 12, 14, 16, 18, 20, 22, and/or 24, or various fragmentsthereof, can be immobilized to a solid support. Proteins added to theassay compete with the binding of the antisera to the immobilizedantigen. The ability of the above proteins to compete with the bindingof the antisera to the immobilized protein is compared to the protein ofSEQ ID NO: 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, and/or 24. The percentcrossreactivity for the above proteins is calculated, using standardcalculations. Those antisera with less than 10% crossreactivity witheach of the proteins listed above are selected and pooled. Thecross-reacting antibodies are then removed from the pooled antisera byimmunoabsorption with the above-listed proteins.

The immunoabsorbed and pooled antisera are then used in a competitivebinding immunoassay as described above to compare a second protein tothe immunogen protein (e.g., the IL-1R like protein of SEQ ID NO: 4, 6,8, 10, 12, 14, 16, 18, 20, 22, and/or 24). In order to make thiscomparison, the two proteins are each assayed at a wide range ofconcentrations and the amount of each protein required to inhibit 50% ofthe binding of the antisera to the immobilized protein is determined. Ifthe amount of the second protein required is less than twice the amountof the protein of the selected protein or proteins that is required,then the second protein is said to specifically bind to an antibodygenerated to the immunogen.

It is understood that these TLR proteins are members of a family ofhomologous proteins that comprise at least 10 so far identified genes.For a particular gene product, such as the TLR2-10, the term refers notonly to the amino acid sequences disclosed herein, but also to otherproteins that are allelic, non-allelic or species variants. It alsounderstood that the terms include nonnatural mutations introduced bydeliberate mutation using conventional recombinant technology such assingle site mutation, or by excising short sections of DNA encoding therespective proteins, or by substituting new amino acids, or adding newamino acids. Such minor alterations must substantially maintain theimmunoidentity of the original molecule and/or its biological activity.Thus, these alterations include proteins that are specificallyimmunoreactive with a designated naturally occurring IL-1R relatedprotein, for example, the TLR proteins shown in SEQ ID NO: 4, 6, 8, 10,12, 14, 16, 18, 20, 22, or 24. The biological properties of the alteredproteins can be determined by expressing the protein in an appropriatecell line and measuring the appropriate effect upon lymphocytes.Particular protein modifications considered minor would includeconservative substitution of amino acids with similar chemicalproperties, as described above for the IL-1R family as a whole. Byaligning a protein optimally with the protein of TLR2-10 and by usingthe conventional immunoassays described herein to determineimmunoidentity, one can determine the protein compositions of theinvention.

VII. Kits and Quantitation

Both naturally occurring and recombinant forms of the IL-1R likemolecules of is invention are particularly useful in kits and assaymethods. For example, these methods would also be applied to screeningfor binding activity, e.g., ligands for these proteins. Several methodsof automating assays have been developed in recent years so as to permitscreening of tens of thousands of compounds per year. See, e.g., aBIOMEK automated workstation, Beckman Instruments, Palo Alto, Calif.,and Fodor, et al., Science 251, 767 (1991), which is incorporated hereinby reference. The latter describes means for testing binding by aplurality of defined polymers synthesized on a solid substrate. Thedevelopment of suitable assays to screen for a ligand oragonist/antagonist homologous proteins can be greatly facilitated by theavailability of large amounts of purified, soluble TLRs in an activestate such as is provided by this invention.

Purified TLR can be coated directly onto plates for use in theaforementioned ligand screening techniques. However, non-neutralizingantibodies to these proteins can be used as capture antibodies toimmobilize the respective receptor on the solid phase, useful, e.g., indiagnostic uses.

This invention also contemplates use of TLR2-10, fragments thereof,peptides, and their fusion products in a variety of diagnostic kits andmethods for detecting the presence of the protein or its ligand.Alternatively, or additionally, antibodies against the molecules may beincorporated into the kits and methods. Typically the kit will have acompartment containing either a defined TLR peptide or gene segment or areagent which recognizes one or the other. Typically, recognitionreagents, in the case of peptide, would be a receptor or antibody, or inthe case of a gene segment, would usually be a hybridization probe.

A preferred kit for determining the concentration of, e.g., TLR4, asample would typically comprise a labeled compound, e.g., ligand orantibody, having known binding affinity for TLR4, a source of TLR4(naturally occurring or recombinant) as a positive control, and a meansfor separating the bound from free labeled compound, for example a solidphase for immobilizing the TLR4 in the test sample. Compartmentscontaining reagents, and instructions, will normally be provided.

Antibodies, including antigen binding fragments, specific for mammalianTLR or a peptide fragment, or receptor fragments are useful indiagnostic applications to detect the presence of elevated levels ofligand and/or its fragments. Diagnostic assays may be homogeneous(without a separation step between free reagent and antibody-antigencomplex) or heterogeneous (with a separation step). Various commercialassays exist, such as radioimmunoassay (RIA), enzyme-linkedimmunosorbent assay (ELISA), enzyme immunoassay (EIA), enzyme-multipliedimmunoassay technique (EMIT) substrate-labeled fluorescent immunoassay(SLFIA) and the like. For example, unlabeled antibodies can be employedby using a second antibody which is labeled and which recognizes theantibody to TLR4 or to a particular fragment thereof. These assays havealso been extensively discussed in the literature.

See, e.g., Harlow and Lane, Antibodies: A Laboratory Manual, CSH.(1988), and Coligan, Current Protocols In Immunology, Greene/Wiley, NewYork (1991).

Anti-idiotypic antibodies may have similar use to serve as agonists orantagonists of TLR4. These should be useful as therapeutic reagentsunder appropriate circumstances.

Frequently, the reagents for diagnostic assays are supplied in kits, soas to optimize the sensitivity of the assay. For the subject invention,depending upon the nature of the assay, the protocol, and the label,either labeled or unlabeled antibody, or labeled ligand is provided.This is usually in conjunction with other additives, such as buffers,stabilizers, materials necessary for signal production such assubstrates for enzymes, and the like. Preferably, the kit will alsocontain instructions for proper use and disposal of the contents afteruse. Typically the kit has compartments for each useful reagent, andwill contain instructions for proper use and disposal of reagents.Desirably, the reagents are provided as a dry lyophilized powder, wherethe reagents may be reconstituted in an aqueous medium havingappropriate concentrations for performing the assay.

The aforementioned constituents of the diagnostic assays may be usedwithout modification or may be modified in a variety of ways. Forexample, labeling may be achieved by covalently or non-covalentlyjoining a moiety which directly or indirectly provides a detectablesignal. In any of these assays, a test compound, TLR, or antibodiesthereto can be labeled either directly or indirectly. Possibilities fordirect labeling include label groups: radiolabels such as ¹²⁵I, enzymes(U.S. Pat. No. 3,645,090) such as peroxidase and alkaline phosphatase,and fluorescent labels (U.S. Pat. No. 3,940,475) capable of monitoringthe change in fluorescence intensity, wavelength shift, or fluorescencepolarization. Both of the patents are incorporated herein by reference.Possibilities for indirect labeling include biotinylation of oneconstituent followed by binding to avidin coupled to one of the abovelabel groups.

There are also numerous methods of separating the bound from the freeligand, or alternatively the bound from the free test compound. The TLRcan be immobilized on various matrixes followed by washing. Suitablematrices include plastic such as an ELISA plate, filters, and beads.Methods of immobilizing the receptor to a matrix include, withoutlimitation, diet adhesion to plastic, use of a capture antibody,chemical coupling, and biotin-avidin. The last step in this approachinvolves the precipitation of antibody/antigen complex by any of severalmethods including those utilizing, e.g., an organic solvent such aspolyethylene glycol or a salt such as ammonium sulfate. Other suitableseparation techniques include, without limitation, the fluoresceinantibody magnetizable particle method described in Rattle, et al. Clin.Chem. 30, 1457 (1984), and the double antibody magnetic particleseparation as described in U.S. Pat. No. 4,659,678, each of which isincorporated herein by reference.

The methods for linking protein or fragments to various labels have beenextensively reported in the literature and do not require detaileddiscussion here. Many of the techniques involve the use of activatedcarboxyl groups either through the use of carbodiimide or active estersto form peptide bonds, the formation of thioethers by reaction of amercapto group with an activated halogen such as chloroacetyl, or anactivated olefin such as maleimide, for linkage, or the like. Fusionproteins will also find use in these applications.

Another diagnostic aspect of this invention involves use ofoligonucleotide or polynucleotide sequences taken from the sequence of aTLR. These sequences can be used as probes for detecting levels of therespective TLR in patients suspected of having an immunologicaldisorder. The preparation of both RNA and DNA nucleotide sequences, thelabeling of the sequences, and the preferred size of the sequences hasreceived ample description and discussion in the literature. Normally anoligonucleotide probe should have at least about 14 nucleotides, usuallyat least about 18 nucleotides, and the polynucleotide probes may be upto several kilobases. Various labels may be employed, most commonlyradionuclides, particularly ³²P. However, other techniques may also beemployed, such as using biotin modified nucleotides for introductioninto a polynucleotide. The biotin then serves as the site for binding toavidin or antibodies, which may be labeled with a wide variety oflabels, such as radionuclides, fluorescers, enzymes, or the like.Alternatively, antibodies may be employed which can recognize specificduplexes, including DNA duplexes, RNA duplexes, DNA-RNA hybrid duplexes,or DNA-protein duplexes. The antibodies in turn may be labeled and theassay carried out where the duplex is bound to a surface, so that uponthe formation of duplex on the surface, the presence of antibody boundto the duplex can be detected. The use of probes to the novel anti-senseRNA may be carried out in any conventional techniques such as nucleicacid hybridization, plus and minus screening, recombinational probing,hybrid released translation (HRT), and hybrid arrested translation(HART). This also includes amplification techniques such as polymerasechain reaction (PCR).

Diagnostic kits which also test for the qualitative or quantitativepresence of other markers are also contemplated. Diagnosis or prognosismay depend on the combination of multiple indications used as markers.Thus, kits may test for combinations of markers. See, e.g., Viallet, etal., Progress in Growth Factor Res. 1, 89 (1989).

VIII. Therapeutic Utility

This invention provides reagents with significant therapeutic value. TheTLRs (naturally occurring or recombinant), fragments thereof, muteinreceptors, and antibodies, along with compounds identified as havingbinding affinity to the receptors or antibodies, should be useful in thetreatment of conditions exhibiting abnormal expression of the receptorsof their ligands. Such abnormality will typically be manifested byimmunological disorders. Additionally, this invention should providetherapeutic value in various diseases or disorders associated withabnormal expression or abnormal triggering of response to the ligand.The Toll ligands have been suggested to be involved in morphologicdevelopment, e.g., dorso-ventral polarity determination, and immuneresponses, particularly the primitive innate responses. See, e.g., Sun,et al., Eur. J. Biochem, 196, 247 (1991); HuItmark, Nature 367, 116(1994).

Recombinant TLRs, muteins, agonist or antagonist antibodies thereto, orantibodies can be purified and then administered to a patient. Thesereagents can be combined for therapeutic use with additional activeingredients, e.g., in conventional pharmaceutically acceptable carriersor diluents, along with physiologically innocuous stabilizers andexcipients. These combinations can be sterile, e.g., filtered, andplaced into dosage forms as by lyophilization in dosage vials or storagein stabilized aqueous preparations. This invention also contemplates useof antibodies or binding fragments thereof which are not complementbinding.

Ligand screening using TLR or fragments thereof can be performed toidentify molecules having binding affinity to the receptors. Subsequentbiological assays can then be utilized to determine if a putative ligandcan provide competitive binding, which can block intrinsic stimulatingactivity. Receptor fragments can be used as a blocker or antagonist inthat it blocks the activity of ligand. Likewise, a compound havingintrinsic stimulating activity can activate the receptor and is thusagonist in that it simulates the activity of ligand, e.g., inducingsignaling. This invention further contemplates the therapeutic use ofantibodies to TLRs as antagonists.

The quantities of reagents necessary for effective therapy will dependupon many different factors, including means of administration, targetsite, physiological state of the patient, and other medicantsadministered. Thus, treatment dosages should be titrated to optimizesafety and efficacy. Typically, dosages used in vitro may provide usefulguidance in the amounts useful for in situ administration of thesereagents. Animal testing of effective doses for treatment of particulardisorders will provide further predictive indication of human dosage.Various considerations are described, e.g., in Gilman, et al., Goodmanand Gilman's: The Pharmacological Bases of Therapeutics, 8th Ed.,Pergamon Press (1990); which is hereby incorporated herein by reference.Methods for administration are discussed therein and below, e.g., fororal, intravenous, intraperitoneal, or intramuscular administration,transdermal diffusion, and others. Pharmaceutically acceptable carrierswill include water, saline, buffers, and other compounds described,e.g., in the Merck Index, Merck & Co., Rahway, N.J. Because of thelikely high affinity binding, or turnover numbers, between a putativeligand and its receptors, low dosages of these reagents would beinitially expected to be effective. And the signaling pathway suggestsextremely low amounts of ligand may have effect. Thus, dosage rangeswould ordinarily be expected to be in amounts lower than 1 mMconcentrations, typically less than about 10 μM concentrations, usuallyless than about 100 nM, preferably less than about 10 pM (picomolar),and most preferably less than about 1 fM (femtomolar), with anappropriate carrier. Slow release formulations, or slow releaseapparatus will often be utilized for continuous administration.

TLRs, fragments thereof, and antibodies or its fragments, antagonists,and agonists, may be administered directly to the host to be treated or,depending on the size of the compounds, it may be desirable to conjugatethem to carrier proteins such as ovalbumin or serum albumin prior totheir administration. Therapeutic formulations may be administered inany conventional dosage formulation. While it is possible for the activeingredient to be administered alone, it is preferable to present it as apharmaceutical formulation. Formulations comprise at least one activeingredient, as defined above, together with one or more acceptablecarriers thereof. Each carrier must be both pharmaceutically andphysiologically acceptable in the sense of being compatible with theother ingredients and not injurious to the patient. Formulations includethose suitable for oral, rectal, nasal, or parenteral (includingsubcutaneous, intramuscular, intravenous and intradermal)administration. The formulations may conveniently be presented in unitdosage form and may be prepared by any methods well known in the art ofpharmacy. See, e.g., Gilman, et al., Goodman and Gilman's: ThePharmacological Bases of Therapeutics, 8th Ed., Pergamon Press (1990);and Avis, et al., Pharmaceutical Dosage Forms: Parenteral Medications,Dekker, N.Y. (1993); Lieberman, et al., Pharmaceutical Dosage Forms:Tablets Dekker, N.Y. (1990); and Lieberman, et al., PharmaceuticalDosage Forms: Disperse Systems Dekker, N.Y. (1990). The therapy of thisinvention may be combined with or used in association with othertherapeutic agents, particularly agonists or antagonists of other IL-1family members.

IX. Ligands

The description of the Toll-like receptors herein provide means toidentify ligands, as described above. Such ligand should bindspecifically to the respective receptor with reasonably high affinity.Various constructs are made available which allow either labeling of thereceptor to detect its ligand. For example, directly labeling TLR,fusing onto it markers for secondary labeling, e.g., FLAG or otherepitope tags, etc., will allow detection of receptor. This can behistological, as an affinity method for biochemical purification, orlabeling or selection in an expression cloning approach. A two-hybridselection system may also be applied making appropriate constructs withthe available TLR sequences. See, e.g., Fields and Song, Nature 340, 245(1989).

Generally, descriptions of TLRs will be analogously applicable toindividual specific embodiments directed to TLR2, TLR3, TLR4, TLR5,TLR6, TLR7, TLR8, TLR9, and/or TLR10 reagents and compositions.

The broad scope of this invention is best understood with reference tothe following examples, which are not intended to limit the inventionsto the specific embodiments.

X. Isolation and Culture of Cells.

Blood CD11C⁺ immature dendritic cells, plasmacytoid pre-dendritic cells,and CD14⁺CD16⁻ monocytes were isolated from human peripheral blood,according to Rissoan, et al., Science 283, 1183 (1999) and Grouard, etal., J. Exp. Med. 185, 1101 (1997). The purity of each cell populationwas over 99%. Monocytes were cultured for five days in RPMI 1640(BioWhittaker, Walkersville, Md.) supplemented with 10% fetal calf serum(BioWhittaker, Walkersville, Md.), 2 mM L-glutamine, 10 mM HEPES, 1 mMsodium pyruvate, 0.055 mM 2-mercaptoethanol, penicillin G, andstreptomycin (Invitrogen Life Technologies, Carlsbad, Calif.), in thepresence of 50 ng/ml GM-CSF (Schering-Plough, Kenilworth, N.J.) and 200U/ml IL-4 (Schering-Plough, Kenilworth, N.J.). The resultingmonocyte-derived immature dendritic cells were washed and cultured for24 h with human CD40L-transfected L cells (irratiated at 5,500 rad) toobtain mature dendric cells type 1 (Rissoan, et al., Science 283, 1183(1999)). Plasmacytoid pre-dendritic cells were cultured for five dayswith 10 ng/ml IL-3 (R & D Systems). The resulting plasmacytoidpre-dendritic cells-derived immature dendritic cells were washed andcultured for 24 h, with CD40L-transfected cells to obtain pre-dendriticcell-derived dendritic cells. To induce the maturation of immaturedendritic cells, the cells were cultured for 24 h with CD40L-transfectedL cells.

To induce cytokine production, cells were cultured for 24 h at two times10⁴/0.2 ml in round-bottom 96-well culture plates in the presence of0.01 mg/ml peptidoglycan from S. aureus (Fluka, Milwaukee, Wis.), 0.01mg/ml lipoteichoic acid (LTA) from S. aureus (Sigma, St. Louis, Mo.),0.01 mg/ml LPS from S. minnesota serotype Re595 (Sigma, St. Louis, Mo.),0.05 mg/ml Poly I:C (Sigma, St. Louis, Mo.), 0.005 mM (0.046 mg/ml)phosphodiester CpG oligodeoxynucleotide (AAC-30) (Yamamoto, et al, Jpn.J. Cancer Res. 85, 775 (1994)). AAC-30 was added at 0, 4, and 16 h tocompensate for degradation by DNase activity in the medium.

XI. Reverse Transcription Polymerase Chain Reaction (RT-PCR)

Reverse transcription polymerase chain reaction for the detection ofmRNA coding for Toll-like receptors was as follows. RNA was isolatedwith the acid guanidinium thiocyanate-phenol-chloroform method(Chomczynski and Sacchi, Anal. Biochem. 162, 156 (1987)). ContaminatingDNA was removed by digestion with 5 U deoxyribonuclease I (BoehringerMannheim) for 30 min at 37° C. Reverse transcription was carried outwith random hexamers (Promega, Madison, Wis.) for priming andSUPERSCRIPT II (Invitrogen Life Technologies, Carlsbad, Calif.). The PCRreaction volume was 0.05 ml, containing 0.5 μM of each primer, 40 nM ofeach deoxynucleoside triphosphate, and 1.25 U AMPLITAQ (Perkin Elmer,Foster City, Calif.). Primers used are shown in Table 1.

TABLE 1 TLR # Sequences of PCR primers. Reverse transcriptase PCRprimers. Forward primers/Reverse primers  1 CGTAAAACTGGAAGCTTTGCAAGACCTTGGGCCATTCCAAATAAGTCC  2 GGCCAGCAAATTACCTGTGTG CCAGGTAGGTCTTGGTGTTCA 3 ATTGGGTCTGGGAACATTTCTCTTC GTGAGATTTAAACATTCCTCTTCGC  4CTGCAATGGATCAAGGACCA TCCCACTCCAGGTAAGTGTT  5 CATTGTATGCACTGTCACTCCCACCACCATGATGAGAGCA  6 TAGGTCTCATGACGAAGGAT GGCCACTGCAAATAAGTCCG  7AGTGTCTAAAGAACCTGG CTTGGCCTTACAGAAATG  8 CAGAATAGCAGGCGTAACACATCAAATGTCACAGGTGCATTCAAAGGG  9 TTATGGACTTCCTGCTGGAGGTGCCTGCGTTTTGTCGAAGACCA 10 CAATCTAGAGAAGGAAGATGGTCCGCCCTTATAAACTTGTGAAGGTGT β-actin ATCTGGCACCACACCTTCTACAATGAGCTGCGCGTCATACTCCTGCTTGCTGATCCACATCTGC Real time PCR primers Forwardprimers/Reverse primers Toll like receptor  2 GGCCAGCAAATTACCTGTGTGAGGCGGACATCCTGAACCT  4 CTGCAATGGATCAAGGACCA TTATCTGAAGGTGTTGCACATTCC  7TTACCTGGATGGAAACCAGCTACT TCAAGGCTGAGAAGCTGTAAGCTA  9TGAAGACTTCAGGCCCAACTG TGCACGGTCACCAGGTTGT

A GENEAMP PCR System 9700 (Perkin Elmer/Applied Biosystems, Foster City,Calif.) was used with an initial denaturation step of 94° C. for 5 min,followed by 35 cycles of 94° C. for 30 sec, 55° C. for 30 sec, 72° C.for 1 min, and a final elongation step of 72° C. for 7 min. PCR productswere separated on a 3% agarose gel containing ethidium bromide. A 1-kbDNA ladder standard (Invitrogen Life Technologies, Carlsbad, Calif.) wasused as a size marker.

XII. Real-Time Quantitative Reverse Transcription PCR

RNA was isolated with the acid guanidinium thiocyanate-phenol-chloroformmethod (Chomczynski and Sacchi Anal. Biochem. 162, 156 (1987)). Thereverse transcription was performed with SUPERSCRIPT II (Invitrogen LifeTechnologies, Carlsbad, Calif.). cDNA was analyzed for the expression ofToll like receptor genes by the fluorogenic 5′-nuclease PCR assay(Rissoan, et al., Science 283, 1183 (1999)) using a Perkin-Elmer ABIPrism 7700 Sequence Detection System (Applied Biosystems, Foster City,Calif.). Reactions were incubated for 2 min at 50° C., denatured for 10min at 95° C., and subjected to 40 two-step amplification cycles withannealing/extension at 60° C. for 1 min, followed by denaturation at 95°C. for 15 sec. The primers used are shown in Table 1. Values areexpressed as arbitrary units (relative to ubiquitin X 1,000).

XIII. Quantitation of Cytokines by ELISA

ELISA kits from the following companies were used to analyze cytokineproduction: TNF-α and IL-6 (R & D Systems, Minneapolis, Minn.) IL-12 andIFN-α (Biosource International, Camarillo, Calif.).

EXAMPLES Example I General Methods

Some of the standard methods are described or referenced, e.g., inManiatis, et al., Molecular Cloning, A Laboratory Manual, Cold SpringHarbor Laboratory, Cold Spring Harbor Press (1982); Sambrook, et al.,Molecular Cloning; A Laboratory Manual, (2d ed.), vols. 1-3, CSH Press,NY (1989); Ausubel, et al., Current Protocols in Molecular Biology,Greene/Wiley, New York (1987). Methods for protein purification includesuch methods as ammonium sulfate precipitation, column chromatography,electrophoresis, centrifugation, crystallization, and others. See, e.g.,Deutscher, “Guide to Protein Purification” in Methods in Enzymology,vol. 182 (1990), and other volumes in this series; and manufacturer'sliterature on use of protein purification products, e.g., Pharmacia,Piscataway, N.J., or Bio-Rad, Richmond, Calif. Combination withrecombinant techniques allow fusion to appropriate segments, e.g., to aFLAG sequence or an equivalent which can be fused via aprotease-removable sequence. See, e.g., Hochuli, Chemische Industrie 12,69 (1989); Hochuli, “Purification of Recombinant Proteins with MetalChelate Absorbent” in Setlow (ed.) Genetic Engineering, Principle andMethods 12, 87 (1990), Plenum Press, N.Y.; and Crowe, et al.,QIAexpress: The High Level Expression and Protein Purification SystemQUIAGEN, Inc., Chatsworth, Calif. (1992).

Standard immunological techniques and assays are described, e.g., inHertzenberg, et al., Weir's Handbook of Experimental Immunology vols.1-4, Blackwell Science (1996); Coligan (1991) Current Protocols inImmunology Wiley/Greene, NY; and Methods in Enzymology volumes, 70, 73,74, 84, 92, 93, 108, 116, 121, 132, 150, 162, and 163.

Assays for vascular biological activities are well known in the art.They will cover angiogenic and angiostatic activities in tumor, or othertissues, e.g., arterial smooth muscle proliferation (see, e.g., Koyoma,et al., Cell 87, 1069 (1996), monocyte adhesion to vascular epithelium(see McEvoy, et al., J. Exp. Med. 185:2069 (1997), Ross, Nature 362, 801(1993); Rekhter and Gordon, Am. J. Pathol. 147, 668 (1995); Thyberg, etal., Atherosclerosis 10, 966 (1990); and Gumbiner, Cell 84, 345 (1996).

Assays for neural cell biological activities are described, e.g., inWouterlood, Neuroscience Protocols modules 10, Elsevier; Methods inNeurosciences Academic Press (1995); and Neuromethods Humana Press,Totowa, N.J. Methodology of developmental systems is described inMeisami, Handbook of Human Growth and Developmental Biology CRC Press(1988).

Computer sequence analysis is performed, e.g., using available softwareprograms, including the GCG WISCONSIN PACKAGE (Accelrys, Inc., SanDiego, Calif.). Public sequence databases were also used, e.g., fromGenBank, NCBI, EMBO, and others. Determination of transmembrane andother important motifs may be predicted using such bioinformatics tools.

Many techniques that have been used, as they relate to interleukin-10receptors, may also be applied to the Toll-like receptors, e.g., U.S.Pat. No. 5,789,192, issued to Moore, et al., U.S. Pat. No. 5,985,828,issued to Moore, et al., and U.S. Pat. No. 5,863,796, issued to Moore,et al., which are incorporated herein by reference for all purposes.

Example II Novel Family of Human Receptors

The discovery of sequence homology between the cytoplasmic domains ofDrosophila Toll and human interleukin-1 (IL-1) receptors suggests thatboth molecules are used in signaling pathways that involve Rel-typetranscription factors. This conserved signaling scheme governs anevolutionarily ancient immune response in both insects and vertebrates.We report the molecular cloning of a novel class of putative humanreceptors with a protein architecture that is closely similar toDrosophila Toll in both intra- and extra-cellular segments. Five humanToll-like receptors, designated TLRs 1-5, are likely the direct homologsof the fly molecule, and as such could constitute an important andunrecognized component of innate immunity in humans; intriguingly, theevolutionary retention of TLRs in vertebrates may indicate another role,akin to Toll in the dorso-ventralization of the Drosophila embryo, asregulators of early morphogenetic patterning. Multiple tissue mRNA blotsindicate markedly different patterns of expression for the human TLRs.Using fluorescence in situ hybridization and Sequence-Tagged Sitedatabase analyses, we also show that the cognate TLR genes reside onchromosomes 4 (TLRs 1, 2, and 3), 9 (TLR4), and 1 (TLR5). Structureprediction of the aligned Toll-homology (TH) domains from varied insectand human TLRs, vertebrate IL-1 receptors, and MyD88 factors, and plantdisease resistance proteins, recognizes a parallel β/α fold with anacidic active site; a similar structure notably recurs in a class ofresponse regulators broadly involved in transducing sensory informationin bacteria.

The study of the Toll receptors of invertebrates and the Toll-likereceptors of mammal, has revealed a family of receptors and signalingpathways that has been maintained during evolution (DeRobertis andSasai, Nature 380, 37 (1996); Arendt and Nübler-Jung, Mech. Develop. 61,7 (1997); Miklos and Rubin, Cell 86, 521 (1996); Chothia, Develop. 1994Suppl., 27 (1994); Banfi, et al., Nature Genet. 13, 167 (1996)). Thestudy of the Toll-like receptors, as they are used in the mammalianimmune system and mammalian development, may be made easier by aknowledge of the role of these receptors in more primitive animals.

A universally critical step in embryonic development is thespecification of body axes, either born from innate asymmetries ortriggered by external cues (DeRobertis and Sasai, Nature 380, 37 (1996);Arendt and Nübler-Jung, Mech. Develop. 61, 7 (1997)). As a model system,particular attention has been focused on the phylogenetic basis andcellular mechanisms of dorsoventral polarization (DeRobertis and Sasai,Nature 380, 37 (1996); Arendt and Nübler-Jung, Mech. Develop. 61, 7(1997)). A prototype molecular strategy for this transformation hasemerged from the Drosophila embryo, where the sequential action of asmall number of genes results in a ventralizing gradient of thetranscription factor Dorsal (St. Johnston and Nüsslein-Volhard, Cell 68,201 (1992); Morisato and Anderson, Ann. Rev. Genet. 29, 371 (1995)).

This signaling pathway centers on Toll, a transmembrane receptor thattransduces the binding of a maternally-secreted ventral factor, Spätzle,into the cytoplasmic engagement of Tube, an accessory molecule, and theactivation of Pelle, a Ser/Thr kinase that catalyzes the dissociation ofDorsal from the inhibitor Cactus and allows migration of Dorsal toventral nuclei (Morisato and Anderson, Ann. Rev. Genet. 29, 371 (1995);Belvin and Anderson, Ann. Rev. Cell Develop. Biol. 12, 393 (1996)). TheToll pathway also controls the induction of potent antimicrobial factorsin the adult fly (Lemaitre, et al., Cell 86, 973 (1996); this role inDrosophila immune defense strengthens mechanistic parallels to IL-1pathways that govern a host of immune and inflammatory responses invertebrates (Belvin and Anderson, Ann. Rev. Cell Develop. Biol. 12, 393(1996); Wasserman, Molec. Biol. Cell 4:767 (1993)). A Toll-relatedcytoplasmic domain in IL-1 receptors directs the binding of a Pelle-likekinase, IRAK, and the activation of a latent NF-κB/I-κB complex thatmirrors the embrace of Dorsal and Cactus (Belvin and Anderson, Ann. Rev.Cell Develop. Biol. 12, 393 (1996); Wasserman, Molec. Biol. Cell 4, 767(1993)).

We describe the cloning and molecular characterization of four newToll-like molecules in humans, designated TLRs 2-5 (following Chiang andBeachy, Mech. Develop. 47, 225 (1994)), that reveal a receptor familymore closely tied to Drosophila Toll homologs than to vertebrate IL-1receptors. The TLR sequences are derived from human ESTs; these partialcDNAs were used to draw complete expression profiles in human tissuesfor the five TLRs, map the chromosomal locations of cognate genes, andnarrow the choice of cDNA libraries for full-length cDNA retrievals.Spurred by other efforts (Banfi, et al., Nature Genet. 13, 167 (1996);and Wang, et al., J. Biol. Chem. 271, 4468 (1996)), we are assembling,by structural conservation and molecular parsimony, a biological systemin humans that is the counterpart of a compelling regulatory scheme inDrosophila. In addition, a biochemical mechanism driving Toll signalingis suggested by the proposed tertiary fold of the Toll-homology (TH)domain, a core module shared by TLRs, a broad family of IL-1 receptors,mammalian MyD88 factors and plant disease resistance proteins. Mitcham,et al., J. Biol. Chem. 271, 5777 (1996); and Hardiman, et al., Oncogene13, 2467 (1996). We propose that a signaling route couplingmorphogenesis and primitive immunity in insects, plants, and animals(Belvin and Anderson, Ann. Rev. Cell Develop. Biol. 12, 393 (1996); andWilson, et al., Curr. Biol. 7, 175 (1997)) may have roots in bacterialtwo-component pathways.

Toll-like receptor (TLR) molecules belong to the IL-1/Toll receptorfamily. Ligands for TLR2 and TLR4 have been identified, and theirfunctions are related to the host immune response to microbial antigenor injury. Takeuchi, et al., Immunity 11, 443 (1999); and Noshino, etal., J. Immunol. 162, 3749 (1999). The pattern of expression of TLRsseem to be restricted. Muzio, et al., J. Immunol. 164, 5998 (2000). Withthese findings that: i) TLR10 is highly expressed and restricted inpDC2s, and ii) pDC2 is the NIPC, it is likely that TLR10 will play animportant role in the host's innate immune response.

Computational Analysis.

Human sequences related to insect TLRs were identified from the ESTdatabase (dbEST) at the National Center for Biotechnology Information(NCBI) using the BLAST server (Altschul, et al., Nature Genet. 6, 119(1994)). More sensitive pattern- and profile-based methods (Bork andGibson, Meth. Enzymol. 266, 162 (1996)) were used to isolate thesignaling domains of the TLR family that are shared with vertebrate andplant proteins present in nonredundant databases.

The progressive alignment of TLR intra- or extracellular domainsequences was carried out by ClustalW (Thompson, et al., Nucleic AcidsRes. 22, 4673 (1994)); this program also calculated the branching orderof aligned sequences by the Neighbor-Joining algorithm (5000 bootstrapreplications provided confidence values for the tree groupings).

Conserved alignment patterns, discerned at several degrees ofstringency, were drawn by the Consensus program (internet URLhttp://www.bork.embl-heidelberg.de/Alignment/consensus.html). The PRINTSlibrary of protein fingerprints(http.//www.biochem.ucl.ac.uk/bsm/dbbrowser/PRINTS/PRINTS.html)(Attwood, et al., Nucleic Acids Res. 25, 212 (1997)) reliably identifiedthe myriad leucine-rich repeats (LRRs) present in the extracellularsegments of TLRs with a compound motif (PRINTS code Leurichrpt) thatflexibly matches N— and C-terminal features of divergent LRRs. Twoprediction algorithms whose three-state accuracy is above 72% were usedto derive a consensus secondary structure for the intracellular domainalignment, as a bridge to fold recognition efforts (Fischer, et al.,FASEB J. 10, 126 (1996)). Both the neural network program PHD (Rost andSander, Proteins 19, 55 (1994)) and the statistical prediction methodDSC (King and Sternberg, Protein Sci. 5, 2298 (1996)) have internetservers (URLs http://www.emblheidelberg.de/predictprotein/phd_pred.htmland http://bonsai.lif.icnet.uk/bmm/dsc/dsc_read_align.html,respectively). The intracellular region encodes the THD regiondiscussed, e.g., Hardiman, et al., Oncogene 13, 2467 (1996); Rock, etal., Proc. Nat'l Acad. Sci. USA 95, 588 (1998), each of which isincorporated herein by reference. This domain is very important in themechanism of signaling by the receptors, which transfers a phosphategroup to a substrate.

Cloning of Full-Length Human TLR cDNAs.

PCR primers derived from the Toll-like Humrsc786 sequence (GenBankaccession code D13637) (Nomura, et al., DNA Res. 1, 27 (1994)) were usedto probe a human erythroleukemic, TF-1 cell line-derived cDNA library(Kitamura, et al., Blood 73, 375 (1989)) to yield the TLR1 cDNAsequence. The remaining TLR sequences were flagged from dbEST, and therelevant EST clones obtained from the I.M.A.G.E. consortium (Lennon, etal., Genomics 33, 151 (1996)) via Research Genetics (Huntsville, Ala.):CloneID#'s 80633 and 117262 (TLR2), 144675 (TLR3), 202057 (TLR4) and277229 (TLR5). Full length cDNAs for human TLRs 2-4 were cloned by DNAhybridization screening of λgt10 phage, human adult lung, placenta, andfetal liver 5′-STRETCH PLUS cDNA libraries (Clontech), respectively; theTLR5 sequence is derived from a human multiple-sclerosis plaque EST. Allpositive clones were sequenced and aligned to identify individual TLRORFs: TLR1 (2366 bp clone, 786 aa ORF), TLR2 (2600 bp, 784 aa), TLR3(3029 bp, 904 aa), TLR4 (3811 bp, 879 aa) and TLR5 (1275 bp, 370 aa).Similar methods are used for TLRs 6-10. Probes for TLR3 and TLR4hybridizations were generated by PCR using human placenta (Stratagene,La Jolla, Calif.) and adult liver (Clontech, Palo Alto, Calif.) cDNAlibraries as templates, respectively; primer pairs were derived from therespective EST sequences. PCR reactions were conducted using T.aquaticus TAQPLUS DNA polymerase (Stratagene, La Jolla, Calif.) underthe following conditions: 1×(94° C., 2 min) 30×(55° C., 20 sec; 72° C.30 sec; 94° C. 20 sec), 1×(72° C., 8 min). For TLR2 full-length cDNAscreening, a 900 bp fragment generated by EcoRI/XbaI digestion of thefirst EST clone (ID#80633) was used as a probe.

Northern Blots (mRNA) and Chromosomal Localization.

Human multiple tissue (Cat#1, 2) and cancer cell line blots(Cat#7757-1), containing approximately 2 μg of poly(A)⁺ RNA per lane,were purchased from Clontech (Palo Alto, Calif.). For TLRs 1-4, theisolated full-length cDNAs served as probes, for TLR5 the EST clone (ID#277229) plasmid insert was used. Briefly, the probes were radiolabeledwith [α-³²P] dATP using the Amersham REDIPRIME random primer labelingkit (RPN1633). Prehybridization and hybridizations were performed at 65°C. in 0.5 M Na₂HPO₄, 7% SDS, 0.5 M EDTA (pH 8.0). All stringency washeswere conducted at 65° C. with two initial washes in 2×SSC, 0.1% SDS for40 min followed by a subsequent wash in 0.1×SSC, 0.1% SDS for 20 min.Membranes were then exposed at −70° C. to X-Ray film (Kodak, Rochester,N.Y.) in the presence of intensifying screens. More detailed studies bycDNA library Southerns (14) were performed with selected human TLRclones to examine their expression in hemopoietic cell subsets.

Human chromosomal mapping was conducted by the method of fluorescence insitu hybridization (FISH) as described in Heng and Tsui, Meth. Molec.Biol. 33, 109 (1994), using the various full-length (TLRs 2-4) orpartial (TLR5) cDNA clones as probes. These analyses were performed as aservice by See DNA Biotech Inc. (Ontario, Canada). A search for humansyndromes (or mouse defects in syntenic loci) associated with the mappedTLR genes was conducted in the Dysmorphic Human-Mouse Homology Databaseby internet server (http://www.hgmp.mrc.ac.uk/DHMHD/hum_chrome1.html).Similar methods are applicable to TLRs 6-10.

Conserved Architecture of Insect and Human TLR Ectodomains.

The Toll family in Drosophila comprises at least four distinct geneproducts. Toll, the prototype receptor involved in dorsoventralpatterning of the fly embryo (Morisato and Anderson, Ann. Rev. Genet.29, 371 (1995)) and a second named ‘18 Wheeler’ (18w) that may also beinvolved in early embryonic development (Chiang and Beachy, Mech.Develop. 47, 225 (1994); Eldon, et al., Develop. 120, 885 (1994)); twoadditional receptors are predicted by incomplete, Toll-like ORFsdownstream of the male-specific-transcript (Mst) locus (GenBank codeX67703) or encoded by the ‘sequence-tagged-site’ (STS) Dm2245 (GenBankcode G01378) (Mitcham, et al., J. Biol. Chem. 271, 5777 (1996)). Theextracellular segments of Toll and 18w are distinctively composed ofimperfect, ˜24 amino acid LRR motifs (Chiang and Beachy, Mech. Develop.47, 225 (1994); and Eldon, et al., Develop. 120, 885 (1994)). Similartandem arrays of LRRs commonly form the adhesive antennae of varied cellsurface molecules and their generic tertiary structure is presumed tomimic the horseshoe-shaped cradle of a ribonuclease inhibitor fold,where seventeen LRRs show a repeating β/α-hairpin, 28 residue motif(Buchanan and Gay, Prog. Biophys. Molec. Biol. 65, 1 (1996)). Thespecific recognition of Spätzle by Toll may follow a model proposed forthe binding of cystine-knot fold glycoprotein hormones by the multi-LRRectodomains of serpentine receptors, using the concave side of thecurved β-sheet (Kajava, et al., Structure 3, 867 (1995)); intriguingly,the pattern of cysteines in Spätzle, and an orphan Drosophila ligand,Trunk, predict a similar cystine-knot tertiary structure (Belvin andAnderson, Ann. Rev. Cell Develop. Biol. 12, 393 (1996); and Casanova, etal., Genes Develop. 9, 2539 (1995)).

The 22 and 31 LRR ectodomains of Toll and 18w, respectively (the Mst ORFfragment displays 16 LRRs), are most closely related to the comparable18, 19, 24, and 22 LRR arrays of TLRs 1-4 (the incomplete TLR5 chainpresently includes four membrane-proximal LRRs) by sequence and patternanalysis (Altschul, et al., Nature Genet. 6, 119 (1994); and Bork andGibson, Meth. Enzymol. 266, 162 (1996)) (FIG. 1). However, a strikingdifference in the human TLR chains is the common loss of a ˜90 residuecysteine-rich region that is variably embedded in the ectodomains ofToll, 18w and the Mst ORF (distanced four, six and two LRRs,respectively, from the membrane boundary). These cysteine clusters arebipartite, with distinct ‘top’ (ending an LRR) and ‘bottom’ (stackedatop an LRR) halves (Chiang and Beachy, Mech. Develop. 47, 225 (1994);Eldon, et al., Develop. 120, 885 (1994); and Buchanan and Gay, Prog.Biophys. Molec. Biol. 65, 1 (1996)); the ‘top’ module recurs in bothDrosophila and human TLRs as a conserved juxtamembrane spacer (FIG. 1).We suggest that the flexibly located cysteine clusters in Drosophilareceptors (and other LRR proteins), when mated ‘top’ to ‘bottom’, form acompact module with paired termini that can be inserted between any pairof LRRs without altering the overall fold of TLR ectodomains; analogous‘extruded’ domains decorate the structures of other proteins (Russell,Protein Engin. 7, 1407 (1994)).

Molecular Design of the TH Signaling Domain.

Sequence comparison of Toll and IL-1 type-I (IL-1R1) receptors hasdisclosed a distant resemblance of a ˜200 amino acid cytoplasmic domainthat presumably mediates signaling by similar Rel-type transcriptionfactors (Belvin and Anderson, Ann. Rev. Cell Develop. Biol. 12, 393(1996); Belvin and Anderson, Ann. Rev. Cell Develop. Biol. 12, 393(1996); Wasserman, Molec. Biol. Cell 4, 767 (1993)). More recentadditions to this functional paradigm include a pair of plant diseaseresistance proteins from tobacco and flax that feature an N-terminal THmodule followed by nucleotide-binding (NTPase) and LRR segments (Wilson,et al., Curr. Biol. 7, 175 (1997)); by contrast, a ‘death domain’precedes the TH chain of MyD88, an intracellular myeloid differentiationmarker (Mitcham, et al., J. Biol. Chem. 271, 5777 (1996); and Hardiman,et al., Oncogene 13, 2467 (1996)) (FIG. 1). New IL-1-type receptorsinclude IL-1R3, an accessory signaling molecule, and orphan receptorsIL-1R4 (also called ST2/Fit-1/T1), IL-1R5 (IL-1R-related protein), andIL-1R6 (IL-1R-related protein-2) (Mitcham, et al., J. Biol. Chem.271:5777 (1996); Hardiman, et al., Oncogene 13, 2467 (1996)). With thenew human TLR sequences, we have sought a structural definition of isevolutionary thread by analyzing the conformation of the common THmodule: ten blocks of conserved sequence comprising 128 amino acids formthe minimal TH domain fold; gaps in the alignment mark the likelylocation of sequence and length-variable loops (FIG. 2A-2B).

Two prediction algorithms that take advantage of the patterns ofconservation and variation in multiply aligned sequences, PHD (Rost andSander, Proteins 19, 55 (1994)) and DSC (King and Sternberg, ProteinSci. 5, 2298 (1996)), produced strong, concordant results for the THsignaling module (FIG. 2A-2B). Each block contains a discrete secondarystructural element: the imprint of alternating β-strands (labeled A-E)and α-helices (numbered 1-5) is diagnostic of a β/α-class fold withα-helices on both faces of a parallel β-sheet. Hydrophobic β-strands A,C and D are predicted to form ‘interior’ staves in the β-sheet, whilethe shorter, amphipathic β-strands B and E resemble typical ‘edge’ units(FIGS. 2A-2B). This assignment is consistent with a strand order ofB-A-C-D-E in the core β-sheet (FIG. 2C); fold comparison (‘mapping’) andrecognition (‘threading’) programs (Fischer, et al., FASEB J. 10, 126(1996)) strongly return this doubly wound β/α topology. A surprising,functional prediction of this outline structure for the TH domain isthat many of the conserved, charged residues in the multiple alignmentmap to the C-terminal end of the β-sheet: residue Asp16 (block numberingscheme—FIG. 2A-2B) at the end of βA, Arg39 and Asp40 following βB, Glu75in the first turn of α3, and the more loosely conserved Glu/Asp residuesin the βD-α4 loop, or after βE (FIG. 2A-2B). The location of four otherconserved residues (Asp7, Glu28, and the Arg57-Arg/Lys58 pair) iscompatible with a salt bridge network at the opposite, N-terminal end ofthe β-sheet (FIG. 2A-2B). Alignment of the other TLR embodiments exhibitsimilar features, and peptide segments comprising these features, e.g.,20 amino acid segments containing them, are particularly important.

Signaling function depends on the structural integrity of the TH domain.Inactivating mutations or deletions within the module boundaries (FIG.2A-2B) have been catalogued for IL-1R1 and Toll (Heguy, et al., J. Biol.Chem. 267, 2605 (1992); Croston, et al., J. Biol. Chem. 270, 16514(1995); Schneider, et al., Genes Develop. 5, 797 (1991); Norris andManley, Genes Develop. 6, 1654 (1992); Norris and Manley, Genes Develop.9, 358 (1995); Norris and Manley, Genes Develop. 10, 862 (1996)). Thehuman TLR1-5 chains extending past the minimal TH domain (8, 0, 6, 22and 18 residue lengths, respectively) are most closely similar to thestubby, 4 aa ‘tail’ of the Mst ORF. Toll and 18w display unrelated 102and 207 residue tails (FIG. 2A-2B) that may negatively regulate thesignaling of the fused TH domains (Norris and Manley, Genes Develop. 9,358 (1995); Norris and Manley, Genes Develop. 10, 862 (1996)).

The evolutionary relationship between the disparate proteins that carrythe TH domain can best be discerned by a phylogenetic tree derived fromthe multiple alignment (FIG. 3). Four principal branches segregate theplant proteins, the MyD88 factors, IL-1 receptors, and Toll-likemolecules; the latter branch clusters the Drosophila and human TLRs.

Chromosomal Dispersal of Human TLR Genes.

In order to investigate the genetic linkage of the nascent human TLRgene family, we mapped the chromosomal loci of four of the five genes byFISH (FIG. 4). The TLR1 gene has previously been charted by the humangenome project: an STS database locus (dbSTS accession number G06709,corresponding to STS WI-7804 or SHGC-12827) exists for the Humrsc786cDNA (Nomura, et al., DNA Res. 1, 27 (1994)) and fixes the gene tochromosome 4 marker interval D4S1587-D42405 (50-56 cM) circa 4p14. Thisassignment has recently been corroborated by FISH analysis. Taguchi, etal., Genomics 32, 486 (1996). In the present work, we reliably assignthe remaining TLR genes to loci on chromosome 4q32 (TLR2), 4q35 (TLR3),9q32-33 (TLR4) and 1q33.3 (TLR5). During the course of this work, an STSfor the parent TLR2 EST (cloneID #80633) has been generated (dbSTSaccession number T57791 for STS SHGC-33147) and maps to the chromosome 4marker interval D4S424-D4S1548 (143-153 cM) at 4q32—in accord with ourfindings. There is a ˜50 cM gap between TLR2 and TLR3 genes on the longarm of chromosome 4.

TLR Genes are Differentially Expressed.

Both Toll and 18w have complex spatial and temporal patterns ofexpression in Drosophila that may point to functions beyond embryonicpatterning (St. Johnston and Nüsslein-Volhard, Cell 68, 201 (1992);Morisato and Anderson, Ann. Rev. Genet. 29, 371 (1995); Belvin andAnderson, Ann. Rev. Cell Develop. Biol. 12, 393 (1996); Lemaitre, etal., Cell 86, 973 (1996); Chiang and Beachy, Mech. Develop. 47, 225(1994); Eldon, et al., Develop. 120, 885 (1994)). We have examined thespatial distribution of TLR transcripts by mRNA blot analysis withvaried human tissue and cancer cell lines using radiolabeled TLR cDNAs(FIG. 5). TLR1 is found to be ubiquitously expressed, and at higherlevels than the other receptors. Presumably reflecting alternativesplicing, ‘short’ 3.0 kB and ‘long’ 8.0 kB TLR1 transcript forms arepresent in ovary and spleen, respectively (FIG. 5, panels A and B). Acancer cell mRNA panel also shows the prominent overexpression of TLR1in a Burkitt's Lymphoma Raji cell line (FIG. 5, panel C). TLR2 mRNA isless widely expressed than TLR1, with a 4.0 kB species detect in lungand a 4.4 kB transcript evident in heart, brain and muscle. The tissuedistribution pattern of TLR3 echoes that of TLR2 (FIG. 5, panel E). TLR3is also present as two major transcripts of approximately 4.0 and 6.0 kBin size, and the highest levels of expression are observed in placentaand pancreas. By contrast, TLR4 and TLR5 messages appear to be extremelytissue-specific. TLR4 was detected only in placenta as a singletranscript of ˜7.0 kB in size. A faint 4.0 kB signal was observed forTLR5 in ovary and peripheral blood monocytes.

Components of an Evolutionarily Ancient Regulatory System.

The original molecular blueprints and divergent fates of signalingpathways can be reconstructed by comparative genomic approaches (Miklosand Rubin, Cell 86, 521 (1996); Chothia, Develop. 1994 Suppl., 27(1994); Banfi, et al., Nature Genet. 13, 167 (1996); Wang, et al., J.Biol. Chem. 271, 4468 (1996)). We have used this logic to identify anemergent gene family in humans, encoding five receptor paralogs atpresent, TLRs 1-5, that are the direct evolutionary counterparts of aDrosophila gene family headed by Toll (FIGS. 1-3). The conservedarchitecture of human and fly TLRs, conserved LRR ectodomains andintracellular TH modules (FIG. 1), intimates that the robust pathwaycoupled to Toll in Drosophila (6, 7) survives in vertebrates. The bestevidence borrows from a reiterated pathway: the manifold IL-1 system andits repertoire of receptor-fused TH domains, IRAK, NF-κB and I-κBhomologs (Belvin and Anderson, Ann. Rev. Cell Develop. Biol. 12, 393(1996); Wasserman, Molec. Biol. Cell 4, 767 (1993); Hardiman, et al.,Oncogene 13, 2467 (1996); Cao, et al., Science 271, 1128 (1996)); atube-like factor has also been characterized. It is not known whetherTLRs can productively couple to the IL-1R signaling machinery, orinstead, a parallel set of proteins is used. Differently from IL-1receptors, the LRR cradle of human TLRs is predicted to retain anaffinity for Spätzle/Trunk-related cystine-knot factors; candidate TLRligands (called PENs) that fit this mold have been isolated.

Biochemical mechanisms of signal transduction can be gauged by theconservation of interacting protein folds in a pathway (Miklos andRubin, Cell 86, 521 (1996); Chothia, Develop. 1994 Suppl., 27 (1994)).At present, the Toll signaling paradigm involves some molecules whoseroles are narrowly defined by their structures, actions or fates: Pelleis a Ser/Thr kinase (phosphorylation), Dorsal is an NF-κB-liketranscription factor (DNA-binding) and Cactus is an ankyrin-repeatinhibitor (Dorsal binding, degradation) (Belvin and Anderson, Ann. Rev.Cell Develop. Biol. 12, 393 (1996)). By contrast, the functions of theToll TH domain and Tube remain enigmatic. Like other cytokine receptors(Heldin, Cell 80, 213 (1995)), ligand-mediated dimerization of Tollappears to be the triggering event: free cysteines in the juxtamembraneregion of Toll create constitutively active receptor pairs (Schneider,et al., Genes Develop. 5, 797 (1991)), and chimeric Torso-Toll receptorssignal as dimers (Galindo, et al., Develop. 121, 2209 (1995)); yet,severe tuncations or wholesale loss of the Toll ectodomain results inpromiscuous intracellular signaling (Norris and Manley, Genes Develop.9, 358 (1995); Winans and Hashimoto, Molec. Biol. Cell 6, 587 (1995)),reminiscent of oncogenic receptors with catalytic domains (Heldin, Cell80, 213 (1995)). Tube is membrane-localized, engages the N-terminal(death) domain of Pelle and is phosphorylated, but neither Toll-Tube orToll-Pelle interactions are registered by two-hybrid analysis (Galindo,et al., Develop. 121, 2209 (1995); Groβhans, et al., Nature 372, 563(1994)); this latter result suggests that the conformational ‘state’ ofthe Toll TH domain somehow affects factor recruitment (Norris andManley, Genes Develop. 10, 862 (1996); and Galindo, et al., Develop.121, 2209 (1995)).

At the heart of these vexing issues is the structural nature of the TollTH module. To address this question, we have taken advantage of theevolutionary diversity of TH sequences from insects, plants andvertebrates, incorporating the human TLR chains, and extracted theminimal, conserved protein core for structure prediction and foldrecognition (FIG. 2). The strongly predicted (β/α)₅ TH domain fold withits asymmetric cluster of acidic residues is topologically identical tothe structures of response regulators in bacterial two-componentsignaling pathways (Volz, Biochemistry 32, 11741 (1993); and Parkinson,Cell 73, 857 (1993)) (FIG. 2A-2C). The prototype chemotaxis regulatorCheY transiently binds a divalent cation in an ‘aspartate pocket’ at theC-end of the core β-sheet; this cation provides electrostatic stabilityand facilitates the activating phosphorylation of an invariant Asp(Volz, Biochemistry 32, 11741 (1993)). Likewise, the TH domain maycapture cations in its acidic nest, but activation, and downstreamsignaling, could depend on the specific binding of a negatively chargedmoiety: anionic ligands can overcome intensely negative binding-sitepotentials by locking into precise hydrogen-bond networks (Ledvina, etal., Proc. Natl. Acad. Sci. USA 93, 6786 (1996)). Intriguingly, the THdomain may not simply act as a passive scaffold for the assembly of aTube/Pelle complex for Toll, or homologous systems in plants andvertebrates, but instead actively participate as a true conformationaltrigger in the signal transducing machinery. Perhaps explaining theconditional binding of a Tube/Pelle complex, Toll dimerization couldpromote unmasking, by regulatory receptor tails (Norris and Manley,Genes Develop. 9, 358 (1995); Norris and Manley, Genes Develop. 10, 862(1996)), or binding by small molecule activators of the TH pocket.However, ‘free’ TH modules inside the cell (Norris and Manley, GenesDevelop. 9, 358 (1995); Winans and Hashimoto, Molec. Biol. Cell 6, 587(1995)) could act as catalytic, CheY-like triggers by activating anddocking with errant Tube/Pelle complexes.

Morphogenetic Receptors and Immune Defense.

The evolutionary link between insect and vertebrate immune systems isstamped in DNA: genes encoding antimicrobial factors in insects displayupstream motifs similar to acute phase response elements known to bindNF-κB transcription factors in mammals (HuItmark, Trends Genet. 9, 178(1993)). Dorsal, and two Dorsal-related factors, Dif and Relish, helpinduce these defense proteins after bacterial challenge (Reichhart, etal., C. R. Acad. Sci. Paris 316, 1218 (1993); Ip, et al., Cell 75, 753(1993); Dushay, et al., Proc. Natl. Acad. Sci. USA 93, 10343 (1996));Toll, or other TLRs, likely modulate these rapid immune responses inadult Drosophila (Lemaitre, et al. (1996) Cell 86:973-983; Rosetto, etal., Biochem. Biophys. Res. Commun. 209, 111 (1995)). These mechanisticparallels to the IL-1 inflammatory response in vertebrates are evidenceof the functional versatility of the Toll signaling pathway, and suggestan ancient synergy between embryonic patterning and innate immunity(Belvin and Anderson, Ann. Rev. Cell Develop. Biol. 12, 393 (1996);Lemaitre, et al., Cell 86, 973 (1996); Wasserman, Molec. Biol. Cell 4,767 (1993); Wilson, et al., Curr. Biol. 7, 175 (1997); HuItmark, TrendsGenet. 9, 178 (1993); Reichhart, et al., C. R. Acad. Sci. Paris 316,1218 (1993); Ip, et al., Cell 75, 753 (1993); Dushay, et al., Proc.Natl. Acad. Sci. USA 93, 10343 (1996); Rosetto, et al., Biochem.Biophys. Res. Commun. 209, 111 (1995); Medzhitov and Janeway, Curr.Opin. Immunol. 9, 4 (1997)). The closer homology of insect and human TLRproteins invites an even stronger overlap of biological functions thatsupersedes the purely immune parallels to IL-1 systems, and lendspotential molecular regulators to dorso-ventral and othertransformations of vertebrate embryos (DeRobertis and Sasai, Nature 380,37 (1996); Arendt and Nübler-Jung, Mech. Develop. 61, 7 (1997)).

The present description of an emergent, robust receptor family in humansmirrors the recent discovery of the vertebrate Frizzled receptors forWnt patterning factors. Wang, et al., J. Biol. Chem. 271, 4468 (1996).As numerous other cytokine-receptor systems have roles in earlydevelopment (Lemaire and Kodjabachian, Trends Genet. 12, 525 (1996)),perhaps the distinct cellular contexts of compact embryos and ganglyadults simply result in familiar signaling pathways and their diffusibletriggers having different biological outcomes at different times, e.g.,morphogenesis versus immune defense for TLRs. For insect, plant, andhuman Toll-related systems (Hardiman, et al., Oncogene 13, 2467 (1996);Wilson, et al., Curr. Biol. 7, 175 (1997), these signals course througha regulatory TH domain that intriguingly resembles a bacterialtransducing engine (Parkinson, Cell 73, 857 (1993)).

In particular, the TLR6 exhibits structural features which establish itsmembership in the family. Moreover, members of the family have beenimplicated in a number of significant developmental disease conditionsand with function of the innate immune system. In particular, the TLR6has been mapped to the X chromosome to a location which is a hot spotfor major developmental abnormalities. See, e.g., The Sanger Center:human X chromosome website http://www.sanger.ac.uk/HGP/ChrX/index.shtml;and the Baylor College of Medicine Human Genome Sequencing websitehttp.//gc.bcm.tmc.edu:8088/cgi-bin/seq/home.

The accession number for the deposited PAC is AC003046. This accessionnumber contains sequence from two PACs: RPC-164K3 and RPC-263P4. Thesetwo PAC sequences mapped on human chromosome Xp22 at the Baylor web sitebetween STS markers DXS704 and DXS7166. This region is a “hot spot” forsevere developmental abnormalities.

Example III Amplification of TLR Fragment by PCR

Two appropriate primer sequences are selected (see Tables 1 through 10).RT-PCR is used on an appropriate mRNA sample selected for the presenceof message to produce a partial or full length cDNA, e.g., a samplewhich expresses the gene. See, e.g., Innis, et al., PCR Protocols: AGuide to Methods and Applications, Academic Press, San Diego, Calif.(1990); and Dieffenbach and Dveksler, PCR Primer: A Laboratory Manual,Cold Spring Harbor Press, Cold Spring Harbor, N.Y. (1995). Such willallow determination of a useful sequence to probe for a full length genein a cDNA library. The TLR6 is a contiguous sequence in the genome,which may suggest that the other TLRs are also. Thus, PCR on genomic DNAmay yield full length contiguous sequence, and chromosome walkingmethodology would then be applicable. Alternatively, sequence databaseswill contain sequence corresponding to portions of the describedembodiments, or closely related forms, e.g., alternative splicing, etc.Expression cloning techniques also may be applied on cDNA libraries.

Example IV Tissue Distribution of TLRs

Message for each gene encoding these TLRs has been detected. See FIGS.5A-5F. Other cells and tissues will be assayed by appropriatetechnology, e.g., PCR, immunoassay, hybridization, or otherwise. Tissueand organ cDNA preparations are available, e.g., from Clontech, MountainView, Calif. Identification of sources of natural expression are useful,as described.

Southern Analysis: DNA (5 μg) from a primary amplified cDNA library isdigested with appropriate restriction enzymes to release the inserts,run on a 1% agarose gel and transferred to a nylon membrane (Schleicherand Schuell, Keene, N.H.).

Samples for human mRNA isolation would typically include, e.g.:peripheral blood mononuclear cells (monocytes, T cells, NK cells,granulocytes, B cells), resting (T100); peripheral blood mononuclearcells, activated with anti-CD3 for 2, 6, 12 h pooled (T101); T cell, TH0clone Mot 72, resting (T102); T cell, TH0 clone Mot 72, activated withanti-CD28 and anti-CD3 for 3, 6, 12 h pooled (T103); T cell, TH0 cloneMot 72, anergic treated with specific peptide for 2, 7, 12 h pooled(T104); T cell, TH1 clone HY06, resting (T107); T cell, TH1 clone HY06,activated with anti-CD28 and anti-CD3 for 3, 6, 12 h pooled (T108); Tcell, TH1 clone HY06, anergic treated with specific peptide for 2, 6, 12h pooled (T109); T cell, TH2 clone HY935, resting (T110); T cell, TH2clone HY935, activated with anti-CD28 and anti-CD3 for 2, 7, 12 h pooled(T111); T cells CD4+CD45RO— T cells polarized 27 days in anti-CD28,IL-4, and anti IFN-γ, TH2 polarized, activated with anti-CD3 andanti-CD28 4 h (T116); T cell tumor lines Jurkat and Hut78, resting(T117); T cell clones, pooled AD130.2, Tc783.12, Tc783.13, Tc783.58,Tc782.69, resting (T118); T cell random γδ T cell clones, resting(T119); Splenocytes, resting (B100); Splenocytes, activated withanti-CD40 and IL-4 (B101); B cell EBV lines pooled WT49, RSB, JY, CVIR,721.221, RM3, HSY, resting (B102); B cell line JY, activated with PMAand ionomycin for 1, 6 h pooled (B103); NK 20 clones pooled, resting(K100); NK 20 clones pooled, activated with PMA and ionomycin for 6 h(K101); NKL clone, derived from peripheral blood of LGL leukemiapatient, IL-2 treated (K106); NK cytotoxic clone 640-A30-1, resting(K107); hematopoietic precursor line TF1, activated with PMA andionomycin for 1, 6 h pooled (C100); U937 premonocytic line, resting(M100); U937 premonocytic line, activated with PMA and ionomycin for 1,6 h pooled (M101); elutriated monocytes, activated with LPS, IFNγ,anti-IL-10 for 1, 2, 6, 12, 24 h pooled (M102); elutriated monocytes,activated with LPS, IFNγ, IL-10 for 1, 2, 6, 12, 24 h pooled (M103);elutriated monocytes, activated with LPS, IFNγ, anti-IL-10 for 4, 16 hpooled (M106); elutriated monocytes, activated with LPS, IFNγ, IL-10 for4, 16 h pooled (M107); elutriated monocytes, activated LPS for 1 h(M108); elutriated monocytes, activated LPS for 6 h (M109); DC 70%CD1a+, from CD34+ GM-CSF, TNFα 12 days, resting (D101); DC 70% CD1a+,from CD34+ GM-CSF, TNFα 12 days, activated with PMA and ionomycin for 1hr (D102); DC 70% CD1a+, from CD34+ GM-CSF, TNFα 12 days, activated withPMA and ionomycin for 6 hr (D103); DC 95% CD1a+, from CD34+ GM-CSF, TNFα12 days FACS sorted, activated with PMA and ionomycin for 1, 6 h pooled(D104); DC 95% CD14+, ex CD34+ GM-CSF, TNFα 12 days FACS sorted,activated with PMA and ionomycin 1, 6 hr pooled (D105); DC CD1a+CD86+,from CD34+ GM-CSF, TNFα 12 days FACS sorted, activated with PMA andionomycin for 1, 6 h pooled (D106); DC from monocytes GM-CSF, IL-4 5days, resting (D107); DC from monocytes GM-CSF, IL-4 5 days, resting(D108); DC from monocytes GM-CSF, IL-4 5 days, activated LPS 4, 16 hpooled (D109); DC from monocytes GM-CSF, IL-4 5 days, activated TNFα,monocyte supe for 4, 16 h pooled (D110); leiomyoma L11 benign tumor(X101); normal myometrium M5 (O115); malignant leiomyosarcoma GS1(X103); lung fibroblast sarcoma line MRC5, activated with PMA andionomycin for 1, 6 h pooled (C101); kidney epithelial carcinoma cellline CHA, activated with PMA and ionomycin for 1, 6 h pooled (C102);kidney fetal 28 wk male (O100); lung fetal 28 wk male (O101); liverfetal 28 wk male (O102); heart fetal 28 wk male (O103); brain fetal 28wk male (O104); gallbladder fetal 28 wk male (O106); small intestinefetal 28 wk male (O107); adipose tissue fetal 28 wk male (O108); ovaryfetal 25 wk female (O109); uterus fetal 25 wk female (O110); testesfetal 28 wk male (O111); spleen fetal 28 wk male (O112); adult placenta28 wk (O113); and tonsil inflamed, from 12 year old (X100).

Samples for mouse mRNA isolation can include, e.g.: resting mousefibroblastic L cell line (C200); Braf:ER (Braf fusion to estrogenreceptor) transfected cells, control (C201); T cells, TH1 polarized(Mel14 bright, CD4+ cells from spleen, polarized for 7 days with IFN-γand anti IL-4; T200); T cells, TH2 polarized (Mel14 bright, CD4+ cellsfrom spleen, polarized for 7 days with IL-4 and anti-IFN-γ; T201); Tcells, highly TH1 polarized (see Openshaw, et al., J. Exp. Med. 182,1357 (1995); activated with anti-CD3 for 2, 6, 16 h pooled; T202); Tcells, highly TH2 polarized (Openshaw, et al., J. Exp. Med. 182, 1357(1995)); activated with anti-CD3 for 2, 6, 16 h pooled; T203); CD44−CD25+ pre T cells, sorted from thymus (T204); TH1 T cell clone D1.1,resting for 3 weeks after last stimulation with antigen (T205); TH1 Tcell clone D1.1, 10 μg/ml ConA stimulated 15 h (T206); TH2 T cell cloneCDC35, resting for 3 weeks after last stimulation with antigen (T207);TH2 T cell clone CDC35, 10 μg/ml ConA stimulated 15 h (T208); Mel14+naive T cells from spleen, resting (T209); Mel14+ T cells, polarized toTh1 with IFN-γ/IL-12/anti-IL-4 for 6, 12, 24 h pooled (T210); Mel14+ Tcells, polarized to Th2 with IL-4/anti-IFN-γ for 6, 13, 24 h pooled(T211); unstimulated mature B cell leukemia cell line A20 (B200);unstimulated B cell line CH12 (B201); unstimulated large B cells fromspleen (B202); B cells from total spleen, LPS activated (B203);metrizamide enriched dendritic cells from spleen, resting (D200);dendritic cells from bone marrow, resting (D201); monocyte cell line RAW264.7 activated with LPS 4 h (M200); bone-marrow macrophages derivedwith GM and M-CSF (M201); macrophage cell line J774, resting (M202),macrophage cell line J774+LPS+anti-IL-10 at 0.5, 1, 3, 6, 12 h pooled(M203); macrophage cell line J774+LPS+IL-10 at 0.5, 1, 3, 5, 12 h pooled(M204); aerosol challenged mouse lung tissue, Th2 primers, aerosol OVAchallenge 7, 14, 23 h pooled (see Garlisi, et al., Clinical Immunologyand Immunopathology 75, 75(1995); X206); Nippostrongulus-infected lungtissue (see Coffman, et al., Science 245, 308 (1989); X200); total adultlung, normal (O200); total lung, rag-1 (Schwarz, et al.,Immunodeficiency 4, 249 (1993)); O205); IL-10 K.O. spleen (see Kuhn, etal., Cell 75, 263 (1991); X201); total adult spleen, normal (O201);total spleen, rag-1 (O207); IL-10 K.O. Peyer's patches (O202); totalPeyer's patches, normal (O210); IL-10 K.O. mesenteric lymph nodes(X203); total mesenteric lymph nodes, normal (O211); IL-10 K.O. colon(X203); total colon, normal (O212); NOD mouse pancreas (see Makino, etal., Jikken Dobutsu 29, 1 (1980); X205); total thymus, rag-1 (O208);total kidney, rag-1 (O209); total heart, rag-1 (O202); total brain,rag-1 (O203); total testes, rag-1 (O204); total liver, rag-1 (O206); ratnormal joint tissue (O300); and rat arthritic joint tissue (X300).

The TLR10 has been found to be highly expressed in precursor dendriticcell type 2 (pDC2). See, e.g., Rissoan, et al., Science 283, 1183(1999); and Siegal, et al., Science 284, 1835 (1999). However, it is notexpressed on monocytes. The restricted expression of TLR10 reinforcesthe suggestions of a role for the receptor in host immune defense. ThepDC2 cells are natural interferon producing cells (NIPC), which producelarge amounts of IFNα in response to Herpes simplex virus infection.

Example V Cloning of Species Counterparts of TLRs

Various strategies are used to obtain species counterparts of theseTLRs, preferably from other primates. One method is by crosshybridization using closely related species DNA probes. It may be usefulto go into evolutionarily similar species as intermediate steps. Anothermethod is by using specific PCR primers based on the identification ofblocks of similarity or difference between particular species, e.g.,human, genes, e.g., areas of highly conserved or nonconservedpolypeptide or nucleotide sequence. Alternatively, antibodies may beused for expression cloning.

Example VI Production of Mammalian TLR Protein

An appropriate, e.g., GST, fusion construct is engineered forexpression, e.g., in E. coli. For example, a mouse IGIF pGex plasmid isconstructed and transformed into E. coli. Freshly transformed cells aregrown in LB medium containing 50 μg/ml ampicillin and induced with IPTG(Sigma, St. Louis, Mo.). After overnight induction, the bacteria areharvested and the pellets containing the TLR protein are isolated. Thepellets are homogenized in TE buffer (50 mM Tris-base pH 8.0, 10 mM EDTAand 2 mM pefabloc) in 2 liters. This material is passed through amicrofluidizer (Microfluidics, Newton, Mass.) three times. The fluidizedsupernatant is centrifuged in a Sorvall GS-3 rotor for 1 h at 13,000rpm. The resulting supernatant containing the TLR protein is filteredand passed over a glutathione-SEPHAROSE column equilibrated in 50 mMTris-base pH 8.0. The fractions containing the TLR-GST fusion proteinare pooled and cleaved with thrombin (Enzyme Research Laboratories,Inc., South Bend, Ind.). The cleaved pool is then passed over aQ-SEPHAROSE column equilibrated in 50 mM Tris-base. Fractions containingTLR are pooled and diluted in cold distilled H₂O, to lower theconductivity, and passed back over a fresh Q-Sepharose column, alone orin succession with an immunoaffinity antibody column. Fractionscontaining the TLR protein are pooled, aliquoted, and stored in the −70°C. freezer.

Comparison of the CD spectrum with TLR1 protein may suggest that theprotein is correctly folded (Hazuda, et al., J. Biol. Chem. 264, 1689(1969)).

Example VII Biological Assays With TLRs

Biological assays will generally be directed to the ligand bindingfeature of the protein or to the kinase/phosphatase activity of thereceptor. The activity will typically be reversible, as are many otherenzyme actions, and will mediate phosphatase or phosphorylaseactivities, which activities are easily measured by standard procedures.See, e.g., Hardie, et al., The Protein Kinase FactBook vols. I and II,Academic Press, San Diego (1995), Calif.; Hanks, et al., Meth. Enzymol.200, 38 (1991); Hunter, et al., Cell 70, 375 (1992); Lewin, Cell 61,743-752 (1990); Pines, et al. (1991) Cold Spring Harbor Symp. Quant.Biol. 56, 449 (1991); and Parker, et al., Nature 363, 736 (1993).Because of the homology of the cytoplasmic domain of the Toll receptorand the cytoplasmic domain of the IL-1 receptor, assays sensitive toIL-1 receptor activity may be suitable for measuring activity of TLRs. Areview of IL-1 receptor mediated activities is available (Dinarello,Blood 87, 2095 (1996)).

Example VIII Preparation of Antibodies Specific for TLR, e.g., TLR4

Inbred Balb/c mice are immunized intraperitoneally with recombinantforms of the protein, e.g., purified TLR4 or stable transfected NIH-3T3cells. Animals are boosted at appropriate time points with protein, withor without additional adjuvant, to further stimulate antibodyproduction. Serum is collected, or hybridomas produced with harvestedspleens.

Alternatively, Balb/c mice are immunized with cells transformed with thegene or fragments thereof, either endogenous or exogenous cells, or withisolated membranes enriched for expression of the antigen. Serum iscollected at the appropriate time, typically after numerous furtheradministrations. Various gene therapy techniques may be useful, e.g., inproducing protein in situ, for generating an immune response.

Monoclonal antibodies may be made. For example, splenocytes are fusedwith an appropriate fusion partner and hybridomas are selected in growthmedium by standard procedures. Hybridoma supernatants are screened forthe presence of antibodies which bind to the desired TLR, e.g., by ELISAor other assay. Antibodies which specifically recognize specific TLRembodiments may also be selected or prepared.

In another method, synthetic peptides or purified protein are presentedto an immune system to generate monoclonal or polyclonal antibodies.See, e.g., Coligan, Current Protocols in Immunology Wiley/Greene (1991);and Harlow and Lane, Antibodies: A Laboratory Manual Cold Spring HarborPress (1989). In appropriate situations, the binding reagent is eitherlabeled as described above, e.g., fluorescence or otherwise, orimmobilized to a substrate for panning methods. Nucleic acids may alsobe introduced into cells in an animal to produce the antigen, whichserves to elicit an immune response. See, e.g., Wang, et al., Proc.Nat'l. Acad. Sci. 90, 4156 (1993); Barry, et al., BioTechniques 16, 616(1994); and Xiang, et al., Immunity 2, 129 (1995).

Example IX Production of Fusion Proteins With TLR, e.g., TLR5

Various fusion constructs are made with TLR5. This portion of the geneis fused to an epitope tag, e.g., a FLAG tag, or to a two hybrid systemconstruct. See, e.g., Fields and Song, Nature 340, 245 (1989).

The epitope tag may be used in an expression cloning procedure withdetection with anti-FLAG antibodies to detect a binding partner, e.g.,ligand for the respective TLR5. The two hybrid system may also be usedto isolate proteins which specifically bind to TLR5.

Example X Chromosomal Mapping of TLRs

Chromosome spreads are prepared. In situ hybridization is performed onchromosome preparations obtained from phytohemagglutinin-stimulatedlymphocytes cultured for 72 h. 5-bromodeoxyuridine is added for thefinal seven hours of culture (60 μg/ml of medium), to ensure aposthybridization chromosomal banding of good quality.

An appropriate fragment, e.g., a PCR fragment, amplified with the helpof primers on total B cell cDNA template, is cloned into an appropriatevector. The vector is labeled by nick-translation with ³H. Theradiolabeled probe is hybridized to metaphase spreads as described byMattei, et al., Hum. Genet. 69, 327 (1985).

After coating with nuclear track emulsion (KODAK NTB₂), slides areexposed, e.g., for 18 days at 4° C. To avoid any slipping of silvergrains during the banding procedure, chromosome spreads are firststained with buffered Giemsa solution and metaphase photographed.

R-banding is then performed by the fluorochrome-photolysis-Giemsa (FPG)method and metaphases rephotographed before analysis.

Alternatively, FISH can be performed, as described above. The TLR genesare located on different chromosomes. TLR2 and TLR3 are localized tohuman chromosome 4; TLR4 is localized to human chromosome 9, and TLR5 islocalized to human chromosome 1. See FIGS. 4A-4D.

Example XI Isolation of a Ligand for a TLR

A TLR can be used as a specific binding reagent to identify its bindingpartner, by taking advantage of its specificity of binding, much like anantibody would be used. A binding reagent is either labeled as describedabove, e.g., fluorescence or otherwise, or immobilized to a substratefor panning methods.

The binding composition is used to screen an expression library madefrom a cell line which expresses a binding partner, i.e., ligand,preferably membrane associated. Standard staining techniques are used todetect or sort surface expressed ligand, or surface expressingtransformed cells are screened by panning. Screening of intracellularexpression is performed by various staining or immunofluorescenceprocedures. See also McMahan, et al., EMBO J. 10, 2821 (1991).

For example, on day 0, precoat 2-chamber permanox slides with 1 ml perchamber of fibronectin, 10 ng/ml in PBS, for 30 min at room temperature.Rinse once with PBS. Then plate COS cells at 2-3×10⁵ cells per chamberin 1.5 ml of growth media. Incubate overnight at 37° C.

On day 1 for each sample, prepare 0.5 ml of a solution of 66 μg/mlDEAE-dextran, 66 μM chloroquine, and 4 μg DNA in serum free DME. Foreach set, a positive control is prepared, e.g., of TLR-FLAG cDNA at 1and 1/200 dilution, and a negative mock. Rinse cells with serum freeDME. Add the DNA solution and incubate 5 hr at 37° C. Remove the mediumand add 0.5 ml 10% DMSO in DME for 2.5 min. Remove and wash once withDME. Add 1.5 ml growth medium and incubate overnight.

On day 2, change the medium. On days 3 or 4, the cells are fixed andstained. Rinse the cells twice with Hank's Buffered Saline Solution(HBSS) and fix in 4% paraformaldehyde/glucose for 5 min. Wash 3× withHBSS. The slides may be stored at −80° C. after all liquid is removed.For each chamber, 0.5 ml incubations are performed as follows. AddHBSS/saponin (0.1%) with 32 μl/ml of 1 M NaN₃ for 20 min. Cells are thenwashed with HBSS/saponin 1×. Add appropriate TLR or TLR/antibody complexto cells and incubate for 30 min. Wash cells twice with HBSS/saponin. Ifappropriate, add first antibody for 30 min. Add second antibody, e.g.,Vector anti-mouse antibody, at 1/200 dilution, and incubate for 30 min.Prepare ELISA solution, e.g., Vector Elite ABC horseradish peroxidasesolution, and preincubate for 30 min. Use, e.g., 1 drop of solution A(avidin) and 1 drop solution B (biotin) per 2.5 ml HBSS/saponin. Washcells twice with HBSS/saponin. Add ABC HRP solution and incubate for 30min. Wash cells twice with HBSS, second wash for 2 min, which closescells. Then add Vector diaminobenzoic acid (DAB) for 5 to 10 min. Use 2crops of buffer plus 4 drops DAB plus 2 drops of H₂O₂ per 5 ml of glassdistilled water. Carefully remove chamber and rinse slide in water. Airdry for a few minutes, then add 1 drop of Crystal Mount and a coverslip. Bake for 5 min at 85-90° C.

Evaluate positive staining of pools and progressively subclone toisolation of single genes responsible for the binding.

Alternatively, TLR reagents are used to affinity purify or sort outcells expressing a putative ligand. See, e.g., Sambrook, et al. orAusubel, et al.

Another strategy is to screen for a membrane bound receptor by panning.The receptor cDNA is constructed as described above. The ligand can beimmobilized and used to immobilize expressing cells. Immobilization maybe achieved by use of appropriate antibodies which recognize, e.g., aFLAG sequence of a TLR fusion construct, or by use of antibodies raisedagainst the first antibodies. Recursive cycles of selection andamplification lead to enrichment of appropriate clones and eventualisolation of receptor expressing clones.

Phage expression libraries can be screened by mammalian TLRs.Appropriate label techniques, e.g., anti-FLAG antibodies, will allowspecific labeling of appropriate clones.

Example XII Differentiation of Pre-Dendritic Cells to Mature MyeloidCells and Differentiation of Naive T Helper Cells to T_(H)1 Cells;Differentiation of Pre-Dendritic Cells to Mature Lymphoid-Type Cells andDifferentiation of Naive T Helper Cells to T_(H)2 Cells.

Dendritic cells participate in the innate immune system, as these cellscontain Toll-like receptors which can respond to molecules specific tobacteria, such as bacterial lipopolysacchardise (endotoxin),lipoteichoic acid, and non-methylated CpG oligonucleotides. Twodifferent types of precursors of dendritic cells can be found humans.These are: (1) Peripheral blood monocytes (pDC1); and (2) CD4⁺CD3⁻CD11c⁻plasmacytoid cells (pDC2). Peripheral blood monocytes (pDC1) give riseto immature myeloid DCs after culturing with GMCSF and IL-4. Theseimmature cells give rise to mature myeloid dendric cells (DC1) afterstimulation with CD40 ligand (CD40L). When the mature myeloid dendriticcells are cultured with naive T helper cells, the naive T helper cellsbecome TH1 type cells, and produce TH1 type cytokines, such as IFN-γ(Rissoan, et al., Science 283, 1183 (1999)).

CD4⁺CD3⁻CD11c⁻ plasmacytoid cells give rise to immature lymphoid-typedendritic cell after culture with IL-3. These immature cells give riseto mature lymphoid-type dendritic cells after stimulation with CD40ligand (CD40L). When the mature lymphoid-type dendritic cells arecultured with naive T helper cells, the naive T helper cells becomeT_(H)2 type cells which, in turn, produce T_(H)2-type cytokines, such asIL-4 (Rissoan, et al., Science 283, 1183 (1999)).

The above description relates to two broad scenarios. The first involvesperipheral blood monocytes (pDC1) and their role, after stimulation, topromote the conversion of naive T-helper cells to T_(H)1 cells. Thesecond scenario involves CD4⁺CD3⁻CD11c⁻ plasmacytoid cells (pDC2) andtheir role, after stimulation, to promote the conversion of naiveT-helper cells to T_(H)2 cells. The above two pathways communicate witheach other in a manner mediated by IL-4 (product of T_(H)2 cells). Withoverproduction of IL-4, or during production of IL-4 during late stagein the immune response, this IL-4 inhibits the differentiation ofCD4⁺CD3⁻CD11c⁻ plasmacytoid cells (pDC2), and in this way feedbackinhibits the production of TH2 type cells. With overproduction of IL-4,or during production of IL-4 during late stage in the immune response,the IL-4 stimulates the conversion of peripheral blood monocytes (pDC1)to immature myeloid dendritic cells, thus increasing the production ofT_(H)1 type cells (Rissoan, et al., Science 283, 1183 (1999)).

Example XIII Natural Interferon Producing Cells

The following commentary concerns some of the characteristics of a lineof CD4⁺CD3⁻ CD11c⁻ plasmacytoid cells, which have been found to be atype of “natural interferon producting cell.” The plasmacytoidmorphology has been shown by Siegal, et al., Science 284, 1835 (1999)).

“Natural interferon producing cells” (IPC) are specialized leucocytesthat are the major source of interferon-α in response to viruses,bacteria, and tumor cells. Another characteristic of natural interferonproducing cells (IPC) is that they express CD4 and Class II MHC.CD4⁺CD3⁻CD11c⁻ type 2 cells have been identified as a type of IPC.CD4⁺CD3⁻CD11c⁻ type 2 cells are dendritic cell precursors are cells thatcan respond to microbial challenge and, when challenged, can produce200-1000 times more interferon than other blood cells after microbialchallenge (Siegal, et al., Science 284, 1835(1999)). Production ofinterferon-α occurs in response to Sendai virus, heat-killed S.aureus,or UV-irradiated virus. The fact that the CD4⁺CD3⁻CD11c⁻ type 2 cellsproduce interferon-α in the absence of other cells suggests that thesecells are part of the innate immune system (Siegal, et al., Science 284,1835(1999)).

Example XIV Subsets of Precursors of Human Dendritic Cells

The following cell lines were studied: (1) CD4⁺CD3⁻CD11c⁺ immaturedendritic cells. Note that these are CD11c⁺; (2) CD4⁺CD3⁻CD11c⁻plasmacytoid pre-dendritic cells (pDC2) (natural interferon producingcells). Note that these are CD11c⁻; and (3) CD14⁺CD16⁻ monocytes (pDC1).

The above-mentioned cells are described by Rissoan, et al., Science 283,1183 (1999) and by Siegal, et al., Science 284, 1835 (1999)).

The present study revealed the forms of Toll like receptors (TLRs) onthe various cells lines, as well as the influences of various addedfactors on the expression of the various TLRs. These factors included:(1) GMCSF plus IL-4 on the TLRs; (2) CD40L; and (3) Interleukin-3(IL-3).

CD4⁺CD3⁻CD11c⁺ immature dendritic cells expressed high levels of TLR1,2, and 3, low levels of TLR 5, 6, 8, and 10, and undetectable levels ofTLR 4, 7, and 9.

CD4⁺CD3⁻CD11c⁻ plasmacytoid pre-dendritic cells (pDC2) expressed highlevels of TLR 7 and 9, low levels of TLR 1, 6, and 10, and undetectablelevels of TLR 2, 3, 4, 5, and 8.

CD14⁺CD16⁻ monocytes (pDC1) expressed high levels of TLR 1, 2, 3, 5, and8, low levels of TLR6, and undetectable levels of TLR 3, 7, 9, and 10.

The following concerns exposure of the cell types to various stimulantsor factors. Where CD14⁺CD16⁻ monocytes (pDC1) are differentiated intoimmature dendritic cells by exposure to GMCSF plus IL-4, the initialhigh expression of TLR2 and TLR4 decreased dramatically, where furtherdecline occurred with CD40L treatment. This decrease in TLR2 and TLR4expression is consistent with the functional switch of the dendriticcell lineage from a microbial antigen recognition to antigenpresentation (presentation to naive T cells).

CD4⁺CD3⁻CD11c⁺ immature dendritic cells express moderate levels of TLR2and TLR4, where expression decreases with exposure to CD40L.

CD4⁺CD3⁻CD11c⁻ plasmacytoid pre-dendritic cells (pDC2), which do notexpress TLR2 or TLR4 at any stages of maturation.

CD4⁺CD3⁻CD11c⁻ plasmacytoid pre-dendritic cells (pDC2) express TLR7 andTLR9, where expression of these two receptors progressively decreaseswith stimulation by IL-3 (to provoke differentiation to immaturedendritic cells) and by CD40L (to provoke further differentiation tomature lymphoid dendritic cells).

Responses to peptidoglycan, lipopolysaccharide, lipoteichoic acid,unmethylated CpG oligonucleotides, and poly I:C were studied.Peptidoglycan (TLR2 ligand) stimulated CD14⁺CD16⁻ monocytes (pDC1) toproduce TNF-α and IL-6. Peptidoglycan stimulated CD4⁺CD3⁻CD11c⁺ immaturedendritic cells to produce TNF-α, and small amounts of IL-6 and IL-12.Peptidoglycan did not stimulate CD4⁺CD3⁻CD11c⁻ plasmacytoidpre-dendritic cells (pDC2) to produce any of the cytokines tested.

Lipotechoic acid (LTA), another TLR2 ligand, was tested. Its effects onthe three cell lines did not exactly parallel those of peptidoglycan.LTA stimulated the monocytes to produce TNF-A and IL-6, but did notstimulate the CD4⁺CD3⁻CD11c⁺ immature dendritic cells to producedetectable levels of the cytokines tested. LTA did not stimulate theplasmacytoid pre-dendritic cells.

Lipopolysaccharide (LPS) is a ligand for TLR-4. LPS stimulated monocytesto produce TNF-α and IL-6. LPS stimulated CD4⁺CD3⁻CD11c⁺ immaturedendritic cells to produce small amounts of IL-12p75, in two out of fourhuman cell donors. LPS did not stimulate the plasmacytoid pre-dendriticcells to produce any of the cytokines tested.

Unmethylated CpG oligonucleotide (AAC-30) is a ligand for TLR9. AAC-30did not stimulate monocytes or CD4⁺CD3⁻CD11c⁺ immature dendritic cellsto produce IFN-α, but did stimulate plasmacytoid pre-dendritic cells toproduce IFN-α.

Poly I:C did not stimulate monocytes, and did not stimulate plasmacytoidpre-dendritic cells, but did stimulate CD4⁺CD3⁻CD11c⁺ immature dendriticcells to produce IFN-α and IL-12p75. Although AAC-30 and poly I:C areboth comprised on nucleic acid, they had dissimilar effects on the threecell lines tested.

Example XV Treatment of Viral Diseases and Tumors

Interferon-α is used to treat a number of viral disease, includinghepatitis B, hepatitis C, hepatitis D (Di Bisceglie, New Engl. J. Med.330, 137 (1994); Hoofnagle and Di Bisceglie, New Engl. J. Med. 336, 347(1997), and T-cell leukemia-lymphoma (Gill, et al., New Engl. J. Med.332, 1744 (1995)). Interferon-α is also useful for treating multiplemyeloma (Bataille and Harousseau, New Engl. J. Med. 336, 1657 (1997) andchronic myeloid leukemia (Faderl, et al., New Engl. J. Med. 341, 164(1999); Porter, et al., New Engl. J. Med. 330, 100 (1994)). Diseases anddisease states that are responsive to treatment with interferon-α may becalled interferon-α treatable conditions.

Activating antibodies (anti-TLR9) are contemplated, where theseantibodies provoke plasmacytoid pre-dendritic cells to secreteinterferon-α. The invention contemplates use of anti-TLR9 to provokeplasmacytoid pre-dendritic cells to secrete interferon-α for use intreating interferon-α responsive diseases, including those describedabove.

Example XVI Treatment of Systemic Lupus Erythematosus by Anti-TLR9 or bySoluble TLR9

Systemic lupus erythematosus (SLE) is a disease involving elevated seruminterferon-α. In SLE, complexes of anti-DNA (autoantibodies) and DNA arefound in the bloodstream (Ronnblom and Alm, Trends in Immunol. 22, 427(2001)). These complexes stimulate natural interferon-α producing cells,e.g., plasmacytoid pre-dendritic cells, where stimulation results in thesecretion of interferon-α. This secreted interferon-α sustains thegeneration of more autoantibodies.

Antibodies to TLR9 are contemplated, where these antibodies areinactivating antibodies, and where the inactivating antibodies inhibitTLR9 and prevent TLR9 ligands from activating the cell to secreteinterferon-α. Also contemplated is use of soluble versions of TLR9 tobind to anti-DNA/DNA complexes, thus preventing these complexes fromactivating TR9 (thus preventing the consequent secretion ofinterferon-α).

Example XVII Treatment of Septic Shock by an Antibody to an TLR-4 or bySoluble TLR-4

Serious infections may result in a system response to the infectioncalled sepsis. When sepsis results in hypotension and organ dysfunction,it is called septic shock (Parrillo, New Engl. J. Med. 328, 1471(1993)). Gram-positive organisms, fungi, and endotoxin-containinggram-negative organisms can initiate a series of events resulting insepsis and septic shock. One feature of septic shock is decreased use ofoxygen by various tissues of the body. Another feature is that manyvascular beds are abnormally dilated, while others are abnormallyconstricted, resulting in maldistribution of blood flow (Parrillo, NewEngl. J. Med. 328, 1471 (1993)).

Endotoxin is a lipopolysaccharide associated with cell membranes of gramnegative microorganisms. Studies with experimental animals and withhumans have shown that endotoxin causes septic shock (Parrillo, NewEngl. J. Med. 328, 1471 (1993)). Endotoxin is a ligand for TLR4(Kadowaki, et al., J. Exp. Med. (in press); Thomas, New Engl. J. Med.342, 664 (2000); Tapping, et al., J. Immunol. 165, 5780 (2000);Supajatura, et al., J. Immunol. 167, 2250 (2001); Hoshino, et al., J.Immunol. 162, 3749 (1999)). Bacterial products have been found which areligands for TLR2. These products, which may contribute to the pathologyof septic shock, have not yet been identified (Tapping, et al., J.Immunol. 165, 5780 (2000)).

It is contemplated to use anti-TLR4 or soluble TLR4 for treating diseaseconditions such as sepsis, where the disease conditions involveinteraction of bacterial, microbial, or fungal products with TLR-4.

Example XVIII Treatment of Septic Shock by an Antibody to an TLR-2 or bySoluble TLR-2

Gram positive organisms can cause sepsis, where the natural productsidentified as causative agents have been identified as peptidoglycan,and lipoteichoic acid (Schwandner, et al., J. Biol. Chem. 274, 17406(1999)). Capsular polysaccharide of Streptococcus, a gram positiveorganism, is a cause of sepsis and neonatal meningitis in Japan (Kogan,et al., J. Biol. Chem. 271, 8786 (1996)). A number of natural productshave been found to stimulate TLR2, including yeast cell walls,spirochetal lipoproteins, whole mycobacteria and mycobacteriallipoarabinomannan, whole gram positive bacteria, and gram positivebacterial lipoteichoic acid, and peptidoglycan (Schwandner, et al., J.Biol. Chem. 274, 17406 (1999); Tapping, et al., J. Immunol. 165, 5780(2000)).

It is also contemplated to use anti-TLR2 or soluble TLR2 for treatingdisease conditions such as sepsis, where the disease conditions involveinteraction of bacterial, microbial, or fungal products with TLR-2.

All citations herein are incorporated herein by reference to the sameextent as if each individual publication or patent application wasspecifically and individually indicated to be incorporated by reference.

Many modifications and variations of this invention can be made withoutdeparting from its spirit and scope, as will be apparent to thoseskilled in the art. The specific embodiments described herein areoffered by way of example only, and the invention is to be limited bythe terms of the appended claims, along with the full scope ofequivalents to which such claims are entitled; and the invention is notto be limited by the specific embodiments that have been presentedherein by way of example.

1. The isolated or recombinant polypeptide comprising the amino acidsequence of SEQ ID NO: 6, or an antigenic fragment thereof.
 2. Anisolated or recombinant nucleic acid encoding a polypeptide comprisingthe amino acid sequence of SEQ ID NO:6 or an antigenic fragment thereof.3. The nucleic acid of claim 2, further comprising an expression vector.4. An antibody or antibody fragment that specifically binds to apolypeptide comprising the amino acid sequence of SEQ ID NO:6 or anantigenic fragment thereof.
 5. (canceled)
 6. The antibody or antibodyfragment of claim 4, wherein said antibody or antibody fragment furthercomprises a detectable label or a purification tag.
 7. The antibody orantibody fragment of claim 4, wherein said antibody or antibody fragmentis attached to a solid support.
 8. A natural allelic variant of apolypeptide comprising the amino acid sequence of SEQ ID NO:6 or anantigenic fragment thereof. 9-22. (canceled)
 23. The polypeptide orantigenic fragment of claim 1, wherein said polypeptide or fragment isdetectably labeled.
 24. The polypeptide or antigenic fragment of claim1, wherein said polypeptide or fragment further comprises anoligopeptide purification tag or a polypeptide purification tag.
 25. Thepolypeptide or antigenic fragment of claim 1, wherein said polypeptideor fragment is attached to a solid support.
 26. The isolated orrecombinant nucleic acid of claim 2, comprising SEQ ID NO:5.